Castiel's Relationships

This is all of Castiel's minor relationships from throughout the series.

Castiel and Anna Milton
They served together in Heaven in the same garrison, with Anna as his captain before she fell. They were probably close, as Castiel states "we have history together".

Castiel and Uriel are later assigned with the task of killing the then-human Anna. Castiel expresses regret and sorrow for having to do this. The mission fails when Anna gets her grace back and escapes them.

The next time Castiel sees her, he tells her he still has orders to destroy her, but she knows that he won't. She questions on whether he thinks what he's doing is right, having Dean torture Alastair. She tries to make him doubt his orders but Castiel becomes angry and states that he is nothing like her, and tells her to leave.

Castiel later calls his sister back and asks her for help on what he should do. She tells him it is time for him to start thinking for himself.

Anna saves Castiel's life during the fight with Uriel by killing the rogue angel. When Anna confronts him about letting Sam out of Bobby Singer's panic room, he betrays her trust and has two angels take her away.

Anna eventually returns to Earth. She resents Castiel for turning her in. Castiel suspects Anna had rejoined the Host though she says otherwise. Castiel stands against her wish to kill Sam Winchester, going so far as to say he will kill her himself if she tries.

This is the last time they see each other before Anna is killed by Michael.

Castiel and Balthazar
They were old friends from their time together in Heaven. Castiel was shocked when he found out Balthazar had rebelled and was moonlighting as a crossroads demon.

After Balthazar rescues him from Raphael, Castiel sets him free from a ring of holy fire which enables him to escape the Winchesters. Afterwards, Balthazar assists Castiel in the war in any and every task given, including saving the Titanic (and later re-sinking it).

Their relationship becomes strained once Balthazar discovers Castiel's alliance with Crowley. Unable to stop Castiel himself, Balthazar becomes a double agent for the Winchesters and eventually betrays his old friend, by giving Sam and Dean Castiel's location.

Castiel then sees his friend as a loose end, and decides to lure Balthazar to a location under the guise of talks before stabbing him to death with an angel blade.

Castiel and Bartholomew


In Heaven, Castiel and Bartholomew were in the same garrison and fought together. Bartholomew was in awe of Castiel and his abilities, but after the fall of the angels, sent other angels and rogue Reapers to hunt Castiel down. With the help of a warding tattoo and Sam and Dean, Castiel managed to avoid Bartholomew's attacks, but was later captured by his followers. To Castiel's surprise, Bartholomew greeted him warmly, even hugging him, having apparently put aside his former anger at Castiel. Bartholomew offers Castiel the chance to help organize the angels under his rule and retake Heaven, believing that together they can do it. Bartholomew also offers Castiel the resources to track down Metatron.

"Bartholomew: Castiel, get your head out of the sand. Do you know why they brought you back from the battlefield? The truth? [...] Our leaders wanted those captives killed, and they knew you'd stand in the way of their order. Said you didn't have it in you. That you couldn't do what needed to be done. But I know different. I know you've changed. Castiel: I'm not a murderer. Bartholomew: You weren't. Not then. But since then, you've slaughtered thousands of angels. You killed Malachi's man for his Grace. Castiel: Who I was, what I did, that's not who I am."

- Bartholomew and Castiel

However, when Bartholomew tortures an angel and refuses to stop killing even innocent peaceful angels, Castiel refuses to help him, declaring that he wants no more part of slaughtering angels. When Bartholomew attacks him, Castiel is able to overpower his former friend but refuses to kill him. However, when Bartholomew attacks him while his back is turned, Castiel is forced to kill him in self-defense. In the aftermath, Castiel's unwillingness to kill and wanting to do things a different way causes some of Bartholomew's followers to see that there is a different way and decide to follow Castiel instead.

Castiel and Claire Novak
Claire's father Jimmy Novak is the chosen vessel of Castiel. Shortly after Dean was rescued from Hell, Castiel communicated with Jimmy and promised his family safety in exchange for possession. Jimmy agreed. Claire came outside the house just after Castiel entered Jimmy, and was coldly informed that he was not her father. Claire watched Castiel walk away, taking her father with him.

Claire was briefly reunited with her father when Castiel was forcibly removed from his vessel, as shown in The Rapture. When demons attack the family, Jimmy pleads to Castiel to help save them. While Claire is tied up, she is approached by Castiel (presumably in a dream) and asked to assent to possession. Claire agrees, and Castiel defeats some of the demons while possessing her.

Castiel intends to keep using Claire in order to spare Jimmy of the torment of being a vessel, but Jimmy refuses. Castiel accepts Jimmy's decision and returns to his former vessel, leaving Claire and allowing her to return to her mother.

Life for Claire becomes difficult after that. Her mother Amelia goes in search for her husband, leaving Claire mostly in the care of her grandmother and later a Group Home. She becomes rebellious and holds a fair bit of hatred towards Castiel. The two do not meet again until a couple of years later, after Hannah inspires Castiel to go check on the Novaks, only to find what a mess they are in.

Claire is initially hostile, but does admit Castiel has become a slightly better person. Castiel is shown to be protective over Claire. When Claire gets into trouble, Castiel does all he can to save her, acting like a father to her, though Claire does not wish him to act as such. When Claire requests for help in finding her mother, Castiel gets Dean and Sam to partake in the search. After finding her, Claire thanks Castiel for helping her as he goes in search for what abducted her mother. This leads to a confrontation with Tamiel and Amelia's subsequent death.

Despite not getting her mother back, Claire finally accepts Castiel, and before departing to go live with Jody, she hugs him goodbye. She takes with her a birthday gift from Castiel, which is a Grumpy Cat toy. She is shown to still have it in Don't You Forget About Me.

Castiel and Crowley
As an angel, Castiel was an enemy to Crowley who was a demon. When Crowley offered a deal to open Purgatory, knowing Castiel needed the souls to win the war in Heaven, the latter refused at first. However, he realized that he needed more power to defeat Raphael and accepted the offer and a secret alliance was formed to stop the reigniting of the Apocalypse.

Castiel helped collect creatures for Crowley to experiment upon, while Crowley gave 50,000 souls from Hell in advance. Eventually, Castiel betrayed Crowley and opened the door to Purgatory himself. Thus, their working relationship ended.

Castiel later declared himself the new God, and killed Raphael before deciding to spare Crowley, saying that he had plans for him. Those plans were that Castiel would control the flow of souls going into Hell, and that Crowley could continue to rule there.

When Crowley encountered the insane Castiel, he was furious to find him still alive, and also angry that the Winchesters were harboring him. However, Crowley left him alone for the time being, stating that it would be no fun to kill him in his crazy state. He asked Sam and Dean to call him when Castiel regained his sanity so they could fight.

At this time, Crowley respected Castiel's wishes for him not to harm Meg. This was probably due to the fact they had a common enemy to fight. The Winchesters needed Castiel, and Castiel was fond of Meg.

When Castiel returned from Purgatory, he faced off with Crowley even in his weakened state. Castiel tried to smite Crowley, terrifying the King of Hell into fleeing. Castiel managed to damage Crowley's plans by breaking The Word of God in half, causing Crowley to only get away with one half.

Crowley later captures Castiel, and shoots him in the gut using bullets made from a melted-down Angel Blade, severely injuring him. Crowley had correctly deduced that Castiel had the angel tablet inside of him, and painfully removes it through the hole his bullet made.

In his weakened state, Castiel manages to escape when Crowley leaves him with a single guard. Later, desperate to save Sam from Gadreel, Castiel works with Crowley to allow them to communicate with Sam, and have him force Gadreel out (having gotten the idea from Crowley's torture of Samandriel). As part of the efforts, Castiel had to burn off Sam's anti-possession tattoo so Crowley could possess him.

The plan to use Crowley to save Sam succeeds, and Sam expels Gadreel. Afterward, following Dean's lead, Castiel lets Crowley go as part of their deal.

During the season 10 finale, Rowena casts the Attack Dog spell on Castiel and has him attack Crowley. The demon King however, survives. They do not meet again until Castiel arrives in Hell following a confrontation with Amara. The next time Crowley sees Castiel, he is possessed by Lucifer.

In Hell's Angel, Crowley helps the Winchesters in freeing Castiel of Lucifer. Crowley enters Castiel's vessel, but finds him depressed. His efforts to get Castiel to expel Lucifer fail, and Crowley himself is soon expelled. The two are reunited and working together again after Amara expels Lucifer herself in the season 11 finale.

Crowley and Castiel meet again in The Foundry. Castiel is unimpressed with this unexpected reunion, but their mutual desire to find Lucifer and send him back to his Cage leads to teamwork. They fail however, to find the archangel due to Rowena's intervention, having banished the archangel elsewhere before they could arrive at the former's location.

With the help of Sam and Dean and Vince Vincente's bandmate Tommy, Castiel and Crowley discover Lucifer's latest plan. Although Castiel finds it unfortunate that he has to work with the demon, he and Crowley nevertheless join forces and try to defeat Lucifer before he can murder the fans gathered at a concert. They are both beaten down and left badly injured in the aftermath of trying to foil Lucifer's plan, though they succeed as he is forced to leave his vessel.

In Stuck in the Middle (With You), when Castiel is mortally wounded by the Lance of Michael, Crowley admits to the Winchesters that he's beginning to grow fond of Castiel. He even goes as far as to destroy the Lance in order to save Castiel, despite wanting to use the Lance against Lucifer.

Castiel and Daphne Allen
After he was resurrected following an explosive death at the hands of the Leviathans, Castiel was found, naked and by the lake, by a woman named Daphne. For reasons unclear, Castiel had no memory of who he was. Daphne took this encounter as a word from God and took care of Castiel, now named "Emmanuel", and soon married him.

Castiel and Daphne lived a relatively peaceful and happy life for months, during which Castiel re-discovered his ability to heal people and Daphne helped with contacting clients. Eventually, Castiel's acts as a healer attracted Dean Winchester, as well as demons, to their home. Dean defeated the demon who was threatening Daphne and was reunited with Castiel, though Castiel had no clue who he was.

Dean urged Castiel to help his brother Sam who was at the hospital, and Daphne permitted him to do this. After Castiel left, Daphne never saw him again, as Castiel would regain his memories in his mission to save Sam Winchester.

Out of Castiel's three lovers, Meg and April, Daphne is the only one with whom Castiel had a successful relationship, as Meg was killed approximately a year later and April was a reaper tasked with killing him. It is unclear if Castiel remembers Daphne, or whether he cares about her at all.

Castiel and Gabriel
The archangel Gabriel was Castiel's older brother and the two seem well acquainted with one another. In their first onscreen appearance together in Changing Channels, Gabriel was trying to manipulate Sam and Dean into saying "yes" to Lucifer and Michael respectively, but he had to keep Castiel out of the way since Sam and Dean did not know his true identity yet. Gabriel's ability to knock Castiel aside and send him away with ease, as well as their apparent familiarity with each other became one of the two pieces of evidence that gave his identity away anyway. Once Gabriel's identity was revealed, the two brothers tensely greeted each other with Castiel showing annoyance after Gabriel mocked his search for their father.

It is unknown how close the two brothers were back in Heaven, but Gabriel is the only one of the four archangels never to make an attempt on Castiel's life, or have a reason to. They do not see each other again after Changing Channels, but an illusion of Gabriel crafted by Metatron does interact with Castiel in Meta Fiction. This Gabriel displays protectiveness, trust and care in Castiel, as most loving older brothers would. Castiel in turn, showed trust and concern for Gabriel too until he discovered that he wasn't real.

Judging by Castiel's relationship with the illusion of Gabriel, it is clear that Gabriel is one of the few angels who actually likes Castiel but, to Castiel's dismay, he was presumed dead like many of his loyal friends and siblings.

Castiel was unaware that Gabriel wasn't truly dead but was instead being held captive by Asmodeus until Arthur Ketch rescued him and brought him to the Winchesters.

In Bring 'em Back Alive, Castiel is reunited with his older brother and is dismayed at his state and tries his best to bring him to his senses. He reads Gabriel's message and learns the latter faked his death to avoid having tethers, during the Apocalypse. Once Gabriel speaks and regains his powers, Castiel is relieved that he is back to normal. Gabriel later saved Castiel and Sam from being killed by Asmodeus by incinerating the demon. Afterwards, Castiel caught him up on everything that has transpired but was dismayed that Gabriel wanted no part in it though wished them luck as he left. Castiel swore to Dean that they'd find Gabriel again.

Castiel and Gadreel
Before their first meeting, Castiel had heard stories about Gadreel, the angel who was assigned to protect the Garden of Eden, only to fail by letting Lucifer in, causing all the disastrous events that followed. Castiel held some resentment towards Gadreel, blaming him for The Apocalypse and for many of the struggles of he had to face because of the angel's failure.

When Gadreel approached Dean and offered to heal Sam through possession, Dean called Castiel to ask if this angel was trust worthy. Since Gadreel was using the name of another angel, Ezekiel, as an alias, Castiel assured Dean that the angel could be trusted.

While posing as Ezekiel, Gadreel resurrected Castiel after he had been killed by the rogue reaper April Kelly though he later told Dean to get Castiel away to hide his identity and protect himself (and by extension Sam).

After Dean realized "Ezekiel" was a traitor and needed to be removed from Sam's body, he had Crowley crack into the angel's factory settings, causing Gadreel to reveal his true name. This set Castiel off into a fit of rage, stopped only by Dean's insistence that their priority was to free Sam.

The two became enemies immediately after due to Gadreel's alliance with Metatron. In an attempt to find the angel's current location, Castiel decided to extract the residue of Gadreel's grace from within Sam, but he chose to abandon this task in favor of sparing Sam, as the grace's removal would revert Sam back to his ill-condition prior to the possession.

Castiel gets captured by Metatron sometime later, but he is set free when the Winchesters manage to capture Gadreel. The two sides agree to make a trade. Later on, Castiel approaches Gadreel and urges him to realize that he is making the same mistake again by following Metatron, but Gadreel refuses to listen, since he cannot surrender his honor. Although his doubts about Metatron grow, he rejoins Metatron soon after and resumes recruiting followers for Metatron's faction.

Metatron then orders Gadreel to force some of Castiel's angels into becoming explosives and using them to kill Metatron's own men, in order to make Metatron look like the victim. While the plan does work, the cruel sacrifice of his own followers drives Gadreel to acknowledge his own mistake. He flees Metatron's side and returns to Castiel. Convinced of Gadreel's sincerity, Castiel agrees to work with Gadreel in infiltrating Heaven and locating the angel tablet, the source of Metatron's power. Castiel offers to pretend to be Gadreel's prisoner, but once they arrive in Heaven, the angels lock them up, not fooled by their guise.

Castiel tries to plead with Hannah to see the wrong in Metatron, whom she now follows. During their conversation, Gadreel chooses to commit suicide to repent for his sins and to give "Heaven a second chance", as well as free Castiel from the neighboring cell. Despite Hannah's pleas, Gadreel sets a bomb off on his chest and destroys part of the prison, freeing Castiel and convincing Hannah on who is the real enemy. It is Gadreel's death that ultimately helps Castiel in exposing Metatron's true nature to the rest of Metatron's followers, leading to the latter's imprisonment. It is safe to say that Castiel is grateful for his brother's sacrifice and no longer thinks poorly of him. During their time in the cells, Castiel also refers to Gadreel as his friend and tells him that he has redeemed himself before learning of Gadreel's intention to sacrifice himself.

Castiel and God


Until recently, Castiel had never met God, but followed his orders out of faith. He was obedient until Dean began putting doubts in his head as to who was really giving the angels their orders. Castiel had always followed orders to the best of his abilities, believing them to be passed down to him from God.

Castiel eventually rebels against Heaven and helps Dean. During this time, he unknowingly meets God who was pretending to be a prophet named Chuck Shurley that had been writing books about the Winchester's heroics, which he seemed to support. While under the guise as Chuck, he noticed Castiel's worried facial expression and placed a hand on his shoulder when he prepared to deal with Raphael but removed it when Castiel gave him a look. In Season 5, Castiel begins to look for God in order to stop Lucifer, using Dean's Amulet, but is severely disenchanted when being led to believe God simply doesn't care about the state of things anymore after the Winchesters spoke to Joshua.

Unlike any angel, Castiel has been brought back to life many times, and he assumes that God himself has revived him which Joshua confirmed. As an apparent reward for his role in averting The Apocalypse, God increases Castiel's power and upgrades him with more power.

While working with Crowley, Castiel asks for God's help, but God doesn't respond. Following this failure to get God's notice, and other previous failures, Castiel takes many souls into himself (including the Leviathans), and declares himself the new God. Power drunk but well meaning, he quite possibly becomes the greatest threat that the world has ever known.

God (apparently) resurrects Castiel after the angel dies due to being possessed by the Leviathans. Although God brings him back with his powers intact, Castiel has no memories for some reason. It becomes apparent later that his identity and memories were just buried, and he is able to regain them by vanquishing demons.

Castiel now believes that this and other resurrections are a punishment that gets worse each time, and that if he dies again, God will continue to bring him back for more punishment.

In Don't Call Me Shurley, God confirms to Metatron that he is the one who kept resurrecting Castiel. He tells Metatron "I've rebuilt Castiel more times than I can count" but adds that "look where that got me." Metatron also believed that Castiel was nevertheless God's favorite angel as he brought that up to him but God's tone and facial reaction implies that he is somewhat disappointed in Castiel for his actions.

As Lucifer's vessel, Castiel becomes aware of God's return and helps in recruiting the angels for God's battle against the Darkness. After Amara banished Lucifer from his body, Castiel formally meets his father face to face for the first time as Chuck. He helped God up and worried for his well being after he had been wounded by Amara and supported his plan to defeat her and remains mostly by God's side following the battle's failure. Castiel sat relatively close to God inside the bar the team gather in while Dean goes on a mission as a ticking time bomb. He notices belatedly when God disappears from the room after being teleported by Amara. Despite being in God's presence for most of the episode, Castiel is not shown to interact with him one-on-one.

Its currently unknown what views Castiel has of God now that he's seen him.

Castiel and Hannah
Castiel meets the angel Hannah after the angels were banished by Metatron's spell, and lured to a location by a noise. Hannah was the sole survivor of a group of angels who refused to join Metatron's side, the rest were killed by Gadreel. Hannah initially attempts to kill Castiel, but is defeated and chooses to join his side.

When Castiel decides to build his army, Hannah acts as his second-in-command. This alliance is shattered when Metatron tricks the angels into losing faith in Castiel, blaming him for the suicide bombing. Hannah does not rejoin Castiel's side until Gadreel sacrifices himself, proving Castiel's cause to be just. Together they are able to overthrow Metatron and re-take Heaven.

Hannah later assists Castiel in gathering rogue angels. Hannah shows concern for Castiel's dwindling grace, but is repeatedly brushed off. An encounter with the husband of Hannah's vessel convinces Hannah to abandon her vessel and return to Heaven, leaving Castiel to continue the search alone, but also inspire Castiel to find his own vessel's family.

Castiel meets Hannah again in a new vessel when Castiel attempts to break Metatron out of prison. Hannah is unsupportive of this plan, but ultimately fails to stop her friend due to Bobby's assistance from the inside. Castiel meets Hannah for the last time following the rise of Amara. Hannah partakes in interrogating Castiel on Metatron's whereabouts, but soon chooses to believe that he does not know. Enraged, Efram kills Hannah. Castiel is left deeply saddened by her death. Castiel immediately avenges Hannah by killing Efram for his actions.

Hester and Inias
Hester and Inias are two angels from Castiel's garrison who appeared in Reading Is Fundamental, with the intention on getting their hands on the newly-designated prophet, Kevin Tran. Both angels were shocked to discover that Castiel was alive, since he was thought to have died after he let loose the Leviathans some time ago.

Hester, the new leader of the garrison, was furious with Castel over the genocide of Raphael's followers, which cost Heaven thousands of angels. After delivering a "big, scary speech", Castiel had vanished. Hester wanted an explanation, but soon realized - along with Inias - that Castiel had lost his sanity.

All three were blasted out of their location by Dean before things could escalate. Castiel managed to return to the Winchesters soon after, though after Meg killed a demon near Rufus' cabin, Hester and Inias were able to track them to their new location.

Hester proclaimed that Castiel had fallen in every way possible, ever since the day he had rescued Dean from Hell. In a fit of rage, Hester assaulted Castiel until he bled. Inias tried to stop her, insisting that there were few angels left, only to be knocked aside. Hester's beatings were stopped when Meg stabbed her in the back with an angel blade, killing her.

Hester would not be the last angel to desire vengeance upon Castiel, and Castiel himself would come to regret every one of his sins mentioned by Hester, from his tenure as God and later on, his part in helping Metatron banish the angels from Heaven.

Inias, on the other hand, became one of the very few angels to care for Castiel, enough to want to welcome him back to the garrison, though Castiel ultimately declined. What exactly became of Inias is unknown, though Castiel believes his entire garrison has been wiped out.

Castiel and Ishim
Ishim, like Anna, was Castiel's superior for a time. In 1901, Ishim convinced Castiel along with a group of other angels that the Seraph Akobel had fathered a Nephilim. The group arrived at Lily Sunder's house and murdered Akobel, while Ishim chose to kill the abomination himself. Although Castiel was not entirely comfortable with the task, he trusted Ishim and believed, for the following hundred years, that he and his siblings had done the right thing.

In 2017, Lily sought revenge against all the angels involved in her daughter's death. Castiel was horrified to learn that Lily's daughter May had been an ordinary human and that Ishim had lied to him, leading to the deaths of many angels and putting innocent blood on Castiel's hands. For a time after their reunion, Ishim seemed to care for Castiel still, despite the latter's involvement in the Fall of the Angels, which damaged Ishim's wings. However, as with Lily, Ishim was possessive, demanding as well as manipulative and tried to kill Dean as he saw Dean as Castiel's weakness. It would be by Castiel's own hands that Ishim met his end, something Castiel had threatened to do to his other superior Anna, but never did.

Aside from Ishim's position as Castiel's superior in both power and rank, it is not clear what their relationship actually was like. Ishim seemed to prefer Castiel's female vessel and in 1901, he appeared to trust Castiel as well. The revelation of Ishim's true nature certainly damaged any positive opinion Castiel ever had of Ishim.

Castiel and Jimmy Novak
After Castiel rescues Dean from Hell, he realizes he cannot communicate with the human unless he obtains a vessel. Castiel tracks down Jimmy Novak, a devout Christian and family man who is able to receive Castiel's messages and communicate with him. The two manage to develop a sense of trust but Jimmy's behavior is met with ridicule by his wife.

Forced to work for Castiel, Jimmy assents to possession and becomes Castiel's vessel for months. The experience is rather unpleasant for Jimmy, who feels like he's "being chained to a comet". Castiel does not alter Jimmy's appearance, simply adding a deep voice as the only indicator that the two are not the same person.

Eventually, Jimmy is freed from possession when the angels decide to drag Castiel back to Heaven for rebellious behavior. Sam and Dean discover Jimmy, who informs them that he no longer wishes to have anything to do with angels, his earlier excitement gone due to the torment he suffered, and his desire to be with his wife and daughter again.

Unfortunately, Jimmy's fate was sealed from the moment Castiel first spoke to him, as his status as an angel vessel drew demons to his family, leading to the possession of his wife and neighbors, and an attempt on his life. Jimmy demanded Castiel to rescue his family as part of their deal to gain Jimmy's consent. Castiel obeyed and took Claire as a vessel while smitting the demons holding the family captive.

Castiel was sympathetic to Jimmy's suffering and offered to spare him of the ordeal and take Claire instead, but Jimmy's love for his daughter drove him to take Castiel back, an act which ultimately cost Jimmy's life when the pair were killed by Lucifer. Castiel was given Jimmy's body to use permanently by God, while Jimmy ascended to Heaven.

Years later, Castiel would attempt again to keep his promise to protect Jimmy's family, only to discover that not only had Castiel ruined Jimmy's life, but also caused the break up of the remaining Novaks, with Amelia having gone searching for Jimmy and leaving Claire in bad company. Eventually, Castiel would remedy this situation and find Claire a better home, while Amelia died and went to Heaven, reunited with Jimmy at long last.

Castiel and Lucifer
When Lucifer rebelled against Heaven, Castiel (a newly created angel at the time) remembers being terrified by the raging archangel. Despite this, Lucifer does know of Castiel and sees him as a brother. When they meet again, which is after Castiel himself rebelled against Heaven, Lucifer traps him in a ring of Holy Oil. Lucifer tries to persuade Castiel to work with him by listing things they have in common. Castiel refuses to listen and is subsequently left in the circle while Meg stays to watch over him so that he doesn't manage to free himself.

The two meet again at Stull Cemetery, where Castiel banishes Michael using holy oil. This enrages Lucifer, who smites Castiel as punishment. God resurrects Castiel, shortly after Lucifer has been imprisoned in his Cage by Sam. For the following two years, Castiel makes certain Lucifer does not escape his prison.

Lucifer does not re-enter Castiel's life until six years after their previous meeting. Sam is trapped in Limbo with Lucifer assaulting him, so Castiel joins Dean in trying to fend off the archangel. Their combined effort is not enough to defeat Lucifer. During the fight, Castiel becomes convinced Lucifer can stop The Darkness just as he claims, and assents to possession right before Rowena finishes the spell intended to send Lucifer back to his Cage. It is unknown if Castiel was even aware what Rowena was doing.

Regardless, Lucifer is anchored to Earth with Castiel as his vessel. Using Castiel, Lucifer is able to reclaim the throne of Hell.

How Castiel was treated while used as a vessel is unclear. When Lucifer attempted to kill Sam in The Vessel, Castiel fought back to keep the archangel from hurting his friend, but gave control back so Lucifer could time travel and save Dean. When Crowley enters Castiel's vessel in Hell's Angel, he finds that the angel is suffering from depression, and is likely got "hooks" inside him. Castiel tells the demon that Lucifer mostly just leaves him alone.

Lucifer remains mostly in control afterwards, though he does not seem to prevent Castiel from discovering what is going on outside, as Castiel becomes aware of God's return and God's plan to defeat The Darkness. Lucifer allows Castiel brief control of their shared vessel when the angels choose not to listen to the archangel, in hopes they would instead listen to Castiel.

The battle ends in God's defeat and when Lucifer attempts to rescue God from Amara's clutches, but is knocked aside and ripped from his vessel. Castiel wakes up shortly after, uncertain of his older brother's whereabouts. He later informs Dean that he was stupid for saying "yes" and that he was only trying to help.

In The Foundry, Castiel discovers traces of Lucifer's whereabouts and, still feeling guilty about releasing the Devil from his prison, decides to go after him alone. Crowley soon joins in since he knows more about Lucifer's current vessel. The two manage to track Lucifer down to a cabin in the woods, but fail to find him since Rowena had banished him away earlier.

When Lucifer announces his plan to host a concert in Los Angeles, Castiel relies on Tommy to give him the location. He, Sam, Dean and Crowley track Lucifer down to Club Meteor to prevent the slaughter of Vince's fans. Castiel joins Crowley in fighting against Lucifer. The archangel taunts Castiel about his lack of self-worth, noting how he knows this since he was once inside the angel, and proceeds to beat both him and Crowley to the ground. Enraged, Castiel follows Lucifer to the stage and tries to attack Lucifer again, only to be disarmed by telekinesis.

Alongside Dean and Sam, Castiel listens to Lucifer's declaration that he will destroy God's toys while making the three of them watch, since he finds the act of slaughtering to be "fun". Castiel is disgusted by this and intends to stop Lucifer anyway he can. He joins Sam and Dean in hunting down Lucifer who has taken possession of the President. Castiel is mortified when he discovers Lucifer has also impregnated said's president's lover, Kelly Kline, and makes an effort to try and convince Kelly to abort the child. After Lucifer is finally defeated, Castiel continues to hunt down Kelly and the child out of fear that the child will wreak havoc. Over time, Castiel comes to realize the child might not be born purely evil, but he is unwilling to take the chance. Lucifer's son, on the other hand, seems to favor Castiel over his former protector Dagon, and grants Castiel the powers to kill Dagon. The child seemingly instructs Castiel to become Kelly's new protector, and has somehow convinced Castiel that the child himself is indeed good.

When Lucifer, actually imprisoned in Crowley's lair at the behest of Crowley, finds out Castiel is with his son as opposed to Dagon, he screams in rage. Immediately after escaping the lair, Lucifer hunts down his son and locates Kelly at a house by the lake. To his misfortune, Sam, Dean and Castiel once again stand in his way. In the ensuing fight, Lucifer manages to kill Castiel using an angel blade, but gets trapped in an alternate reality by Mary Winchester.

"Castiel: The last time we were together, you killed me. Lucifer: The last time we were together, you stabbed me."

- Castiel and Lucifer discuss their last meeting

Following Lucifer's return to the main reality, he rescues Castiel from three hostile angels though it costs him a great deal of energy in his weakened state. Castiel was shocked and angered to see his brother again, nearly killing him for revenge for his previous deaths but Lucifer who was surprised to see Castiel resurrected, stopped him as he wasn't that weak. They talked explaining how they are both back after their previous encounter as Lucifer tells him of an impending threat. Following this, Castiel reluctantly sits with Lucifer to talk about Jack despite their differences, apologizing sarcastically for stabbing Lucifer the last time they met. Before Asmodeus captures them, Castiel appears to be willing to put aside his differences with Lucifer for Jack's sake and due to the threat of the alternate Michael.

While held captive by Asmodeus, Castiel and Lucifer develop an exasperated banter with Castiel often chastising Lucifer over his useless threats and Lucifer attempting to get Castiel to give up some of his grace to restore Lucifer's powers. Castiel also takes the opportunity to describe Jack and what he is like to his father, noting that Jack looks more like Kelly than Lucifer. After discovering that rage allows Lucifer to access some of his powers, the two rogue angels team up together to escape, taking down Dipper together and then fighting side-by-side against four more demons and winning. However, Castiel continues to refuse to trust Lucifer given the fact that he trusted Lucifer when they fought the Darkness together and Lucifer betrayed him. After Lucifer tries to take Castiel's grace by force, promising to leave Castiel some, Castiel impales Lucifer with an angel blade, apparently causing Lucifer harm in his weakened state. Castiel tells Lucifer that his actions are Castiel "learning from my mistakes."

Lucifer escaped the are as Castiel searched for him but lost sight of him and collapsed from his injuries. Despite this betrayal, Castiel believed Lucifer's warning of Michael as he saw the fear in his explanation of the latter and didn't hesitate to warn the Winchesters as well.

After locating him, Castiel gave Lucifer an angry look after the latter was relieved to see him alive. Lucifer was nearly captured but with help of Anael, he was able to overpower and torture Castiel and the Winchesters before Ketch came to their aid.

Castiel and Mary Winchester
Castiel's thoughts and opinions on Mary during his time with Dean are non-existent, though in Season 5, Castiel does assist the brothers in time travelling to the past in order to protect Mary from his former captain turned-enemy, Anna Milton. As he is weakened by the journey, Castiel does not get to meet Mary.

Similar to how Mary predicted, Castiel is an angel who does his best to watch over Dean. He visits Mary's grave briefly when he and Sam bid Dean farewell during Dean's suicide mission in Season 11.

Castiel and Mary meet face to face in Season 12, when Castiel returns to the Bunker after being banished by Lady Toni Bevell. There, he encounters a hostile Mary, but also Dean, whom he thought had died in his mission. Dean introduces Castiel to Mary, describing him as an angel with a harp, which Castiel denies having. Despite their turbulent meeting, Mary comes to accept Castiel as part of the family, and together they go and rescue Sam from the British Men of Letters.

Castiel and Mary share a mutual understanding in what it is like to live in a place one is unfamiliar with. Despite years of living as a rogue angel and a family friend of the Winchesters, Castiel does not feel like he truly belongs, similar to Mary, who has lost 33 years of her life and cannot cope with the loss of her husband and the change in her sons. Castiel insists Mary does belong, but she kindly brushes him off.

For a time, both Castiel and Mary split from Sam and Dean. Castiel seeks to undo his mistake of freeing Lucifer by capturing him, while Mary seeks to find a means to adapt in this strange new world by being on her own. When they both finally return to the Bunker, Mary is horrified to learn that Castiel has lost track of Sam and Dean and accuses him of not doing his job. The two are forced to wait for days for a call that may never come. When Alicia Banes calls for help on a werewolf case, Castiel fails to complete it, so Mary takes over.

After six weeks, the two decide to work with the British Men of Letters, specifically Arthur Ketch and Mick Davies. The two men help them find Sam and Dean's location, tracking them after Dean had finally called Castiel. Mary and Castiel are reunited with Sam and Dean just outside Site 94, but on their way back, they are intercepted by Billie the Reaper, who reveals that Dean had made a deal to sacrifice himself in order to escape the prison. Mary offers to go to The Empty to spare both her sons, but Castiel doesn't allow it, and kills Billie to spare all three Winchesters of death. Mary and her sons were shocked by his actions as he states they mean too much to him and he can't afford to let them die.

When Mary chooses to work for the British Men of Letters, she is given the task of stealing The Colt from Ramiel. She convinces Sam, Dean and Castiel to join her by saying that she simply needs help killing this powerful demon. The three go along with her, but the plan somewhat backfires when Ramiel attacks Castiel using the Lance of Michael. Castiel is left dying while Mary is devastated. Castiel is saved when Crowley destroys the Lance, but when Mary returns to Arthur Ketch she expresses her disdain, noting how the mission nearly cost her one of "her boys", meaning Castiel, whom she now regards as family.

In Various & Sundry Villains, while captured Castiel inquires from Lucifer about the Alternate Michael and is made aware that Michael has Mary and is torturing her before he angrily cuts Lucifer off from telling him more.

After escaping, Castiel informs the Winchesters of Michael's invasion and when asked about Mary, he could only tell them she was while holding back some of the details of her status but the brothers see through it and become determine to save her.

Castiel and Metatron
Castiel knew little of the Scribe prior to their meeting, having neither a negative nor a positive opinion about him. All he knew was that Metatron had created the tablets and knew all that was written on them, and Metatron used this knowledge to lure Castiel into trusting him.

By that point, Castiel was suffering from a deep sense of self-loathing, having just survived manipulation by Naomi, lost the angel tablet to Crowley and made Dean angry at him, Castiel's greatest desire was to atone for his sins, and Metatron offered him a solution: complete the three trials that would lock up Heaven, so the angels would no longer cause problems on Earth.

Castiel readily agreed, given that Sam was already doing the trials for locking up Hell. Castiel gathered various ingredients, but by the time Kevin Tran found out that said ingredients weren't listed on the angel tablet, Castiel was already one ingredient away from what Metatron needed for his master plan. Metatron captured the angel and extracted his grace, not to lock up Heaven, but to expel all the angels from Heaven so he could rule over it.

Castiel was banished to Earth, now human, as forced to watch as millions of his siblings fell to Earth with their wings being torn off. Castiel blamed himself entirely for falling for Metatron's trickery, and he wanted nothing more but to get back at Metatron. Metatron, on the other hand, wanted to make Castiel the villain of the story, and tried to use various methods to get the angels to turn against Castiel and work for him. This plan backfired when his unorthodox methods alienated his most trusted follower, Gadreel, who then sided with Castiel.

Gadreel helped Castiel get into Heaven where the latter intended to locate the angel tablet and destroy it, thus stripping Metatron of his power source. While Castiel searched Metatron's office, Metatron arrived and captured him, and proceeded to gloat about having murdered Dean, the human Castiel so dearly loved. Castiel was mortified, but he had, prior to being captured, turned on the radio. When Metatron also gloated about his true intentions and his lack of actual concern for their siblings, all the angels heard it, and proceeded to arrest Metatron and put him in prison.

This was not the last of Metatron, as Castiel was driven to retrieve Metatron from his prison in hopes that he knew the cure to the Mark of Cain. He did not, but he did know the location of Castiel's remaining grace. Despite losing the demon tablet, Castiel was able to regain what was left of his original grace and merge it with "borrowed" grace from Adina, and become a Seraph once again.

Metatron himself, during interrogation, was stripped of his own grace and rendered human, forcing him to suffer through mundane human problems for more than a year until Castiel found him, now working as a videographer. Castiel beat information out of Metatron in order to find out the identity of The Darkness. Metatron revealed that she was God's sister. Feeling that Metatron was too pathetic to kill, Castiel let him go. This was the last time to two ever saw each other.

Regardless, by letting Metatron live, Metatron ended up in hospital and discovered a new perception of life. He became nicer, more loving and less selfish. When God called upon him to become his editor, Metatron chose to demand God to help his creations from his rampaging sister, leading God to meet the Winchesters formally for the first time. It was Metatron too, who joined the rescue mission for Lucifer, who was by then in possession of Castiel's vessel. By taking part in this mission, Metatron helped to rescue Castiel as well. He died trying to buy the gang time to escape when Amara, who had been the one to imprison Lucifer/Castiel, returned to her lair.

Castiel and Michael
For the majority of Castiel's early life, Castiel was led to believe that every order given out was from God. In reality, his older brother the Archangel Michael was in charge of Heaven due to God's absence. In 2008, Castiel and his garrison were given the task of raising Dean Winchester from Hell. Castiel was then ordered to watch over Dean and pass on orders to him from Heaven. Castiel did all of this thinking it was God's will.

When Castiel began acting out on his own will, Heaven captured him and re-programmed him into obeying Heaven's orders. It was during this time that Castiel learned that God was absent and everything he knew about Heaven was a lie. Castiel rebelled, and sided with the Winchester brothers against Heaven. Everything he did following this was in direct confrontation to what Michael wanted. His greatest act of defiance was making sure Dean never said "yes" to Michael.

Castiel met Michael face to face when he arrived at Stull Cemetery to prevent Michael from fighting his brother Lucifer. Castiel tossed a molotov cocktail made of holy oil at Michael, causing him great pain and forcing him to vanish from the field. This enraged Lucifer, who responded by smiting the angel.

After Michael and Lucifer were imprisoned and he was resurrected, Castiel sought to help un-brainwash his siblings from Michael's false teachings, but the effort was in vain. Furthermore, Raphael intended to free both Michael and Lucifer from the Cage in order to restart The Apocalypse. This led to a second civil war in Heaven, as Castiel tried to prevent this from happening.

When Castiel discovered that Sam's soul was still stuck in the Cage, he is the first and so far the only person to assume that Michael took part in torturing Sam before his soul was retrieved. Once Castiel obliterated Raphael, Michael's chances of escaping The Cage seemed to have faded completely. Years later, a weapon crafted by Michael would be used by Ramiel to attack Castiel. The effects of the lance slowly killed Castiel, until Crowley destroyed the lance and saved Castiel from death.

Castiel and Alternate Michael
While Castiel has made no mention of the original Michael in a long time, he has learned from Lucifer that the Michael from an alternate reality wishes to invade their world and wreak havoc. Though reluctant to believe this, Castiel wanted to share the news with Dean and Sam but Lucifer prevented him.

After their capture by Asmodeus, Castiel still remained skeptical of Michael's invasion until Lucifer compares him to their own Michael stating once he settles on something he does it. He is also made aware that the latter has Mary Winchester and is torturing her before he angrily cuts Lucifer off from telling him more.

After escaping Asmodeus and being attacked by Lucifer, Castiel returns to the Winchesters and tells them Michael is coming and Lucifer's fearful warnings confirm it. Castiel also proceeded to aid the brothers in creating a rift to Apocalypse World, in order to save Mary and Jack (who was sent there as well) from Michael.

During ''Bring 'em Back Alive, Castiel is relieved to hear from Dean that Michael doesn't have Jack anymore.

Castiel and Raphael
Ever since Raphael killed Castiel in Lucifer Rising, the two have been enemies. Before Castiel rebelled, it is believed Castiel probably respected Raphael, due to rank and power. After being killed and resurrected, Castiel seeks out Raphael in order to question him on God's whereabouts. Dean assist him on this task and when they track him, Castiel traps Raphael demanding answers but gets none. He then leaves as his brother tries to threaten him but Castiel only responds with a taunt which gets praise from Dean.

Their hatred for one another escalates when Raphael decides to restart the Apocalypse following its collapse, which Castiel refuses to let happen. Through a deal with Crowley, he starts a civil war in Heaven. The battle ends in Castiel's favor after he manages to trick Raphael and absorb the souls of Purgatory for himself.

With Castiel now more powerful than him, Raphael pleas to Castiel by calling him his family and ask if he'd really align with Crowley than sparing his own brother. Castiel ignores Raphael's pleas by smiling at his fear and kills Raphael in a similar manner he himself was killed two years prior, obtaining his revenge.

Castiel and Rowena
Castiel formally met Rowena when Sam gathered the two of them - plus Charlie - to take part in a secret task of freeing Dean from the Mark of Cain. Both Castiel and Rowena showed dislike in each other almost instantly. He was essentially guarding Rowena while watching over Charlie. At Charlie's request, Castiel eventually relocated Rowena to a separate room, only to realize Charlie had fled during that time. Charlie subsequently died after getting cornered by a Styne, but the task continued thanks to Charlie's notes.

Rowena completed it by performing the spell that removed the Mark from Dean. With no obligations left, Rowena cast the Attack Dog Spell on Castiel, forcing him to viciously attack, and attempt to kill Crowley. After he had seemingly completed this task, side-effects of the spell still sent Castiel into fits of blood-thirsty rage, leading him to kill several people. It wasn't until Sam threatened to kill Rowena was Castiel finally freed from the spell.

Later on, Rowena formed an alliance with Lucifer, intent on helping the archangel escape his prison. This led Castiel into confrontation with his older brother, and in a fit of despair, he consented to possession. The payback was Rowena's own, brief demise.

From then on, Castiel and Rowena only interacted when called upon by Sam and Dean to help them deal with a problem. Their next alliance was assisting God in his plan to re-imprison the Darkness. Another alliance was formed in an effort to lock up Lucifer, to whom Rowena no longer held any loyalties, and whose freedom Castiel blamed on himself.

Castiel and Uriel
They worked together during the breaking of the 66 seals. They were from the same garrison. Castiel, for the most part, was Uriel's superior, and stopped Uriel from hurting Sam and Dean many times. Uriel had a strong dislike of human beings, calling them "mud monkeys".

Uriel went rogue and tried to convert Castiel to his own plan of helping Lucifer destroy mankind. Castiel refused, and the two sworn rivals then engaged in a bitter fight to the death. Just when it looked like Castiel was about to be defeated and killed, former angel Anna Milton came up and stabbed Uriel, killing him and saving Castiel's life.

Castiel and Jack
"Jack, your mother, she believed that you would do amazing things, she said that you would change the world for the better. And now, looking at you, talking to you, I know she was right. That we were right. Kelly would be so proud of you."

- Castiel to Jack Initially, Castiel saw the unborn Jack as a potential danger to the world and attempted to kill him and his mother Kelly Kline out of fear of what would occur if he was born, Castiel later saw a new view of the child and desired to protect him from danger such as with Dagon. Castiel received a boost of power from Jack and killed the demon, which had him see that the child wasn't evil. Castiel vowed to protect Jack making sure Lucifer doesn't get near him even briefly turning against Sam and Dean.

Having gained faith in Jack's goodness, Castiel dutifully took care of Kelly up until the end of her pregnancy. In Twigs & Twine & Tasha Banes, Dean expresses his view of Castiel's faith in Jack as Castiel being manipulated due to Castiel's initial fear of him.

In All Along the Watchtower, Castiel expresses faith in jack again when assuring Sam and dean that the child will close the door to the apocalyptic world which his birth opened, when dean questions this, Castiel tells him he has faith. Castiel assures Kelly that he will give his life for her son and to raise him into someone she will be proud of. However, due to his death at Lucifer's hands, Castiel was unable to see Jack being born and couldn't care for him.



At the end of Patience, while Sam and Dean were arguing about him, Jack overheard them mention Castiel and learned that dean's dislike in him stems from the fact that it was Castiel's trust in jack which caused Castiel's death. This caused him to say his name. Castiel was awoken from his slumber in The Empty after hearing Jack's voice calling his name.

During The Big Empty, having been awoke by Jack, Castiel wandered through The Empty and came face to face with Cosmic Entity. Castiel demanded his release from the realm and when he did not give up in doing so, he was resurrected by the entity and sent back to earth.

In Tombstone, a resurrected Castiel comes into contact with the Winchesters who are shocked at him being alive. Castiel learned that it was not Winchesters who played a part in his resurrection but Jack. He returns to the Bunker with them and finally meets his nephew who is shocked to see him alive and Castiel thanks him for his part in bringing him back. In response, Jack hugs Castiel, extremely happy to finally meet him and shows what he has learned from his time with the Winchesters. While working on an assignment, Jack and Castiel catch up with Castiel apologizing for not being there when he needed him but the latter assured him it was alright as he understood it wasn't by choice. When Jack accidentally killed an innocent, Castiel tried to comfort him but Jack couldn't accept it and left both Castiel and the Winchesters.

During War of the Worlds, Castiel searched for Jack, even seeking out other angels to find him. When Duma offers him help, on the condition that Jack help the angels rebuild their kind whose numbers were depleting because of Metatron causing Fall of the Angels. Castiel immediately refused even though he was offered the chance to return to Heaven but he didn't want Jack to be a slave for anyone, which resulted in a fight. After he was saved by Lucifer from Duma and her angels, Castiel spoke with his brother and refused to let him anywhere near his son despite Lucifer telling him of an impending threat.

In The Bad Place, Jack states that he only sees Castiel and the Winchesters as his true family instead of Lucifer and the other angels.

While held captive in Various & Sundry Villains, Castiel voices his views of Jack with some being that he is not evil and he'd turn away from Lucifer if given the chance.

In Devil's Bargain, after escaping Asmodeus and being attacked by Lucifer, Castiel returns to the Winchesters and tells them Michael is coming and Lucifer's warnings confirm it. Castiel also proceeded to aid the brothers in creating a rift to Apocalypse World, in order to save Mary and Jack (who was sent there as well) from Michael. In a talk with Dean, Castiel brought up his promise to Kelly Kline that he would protect her son no matter what and intends to keep that promise. To this end, Castiel is ready to travel back to the apocalypse world to rescue Jack.

Trivia

 * Most of Castiel's relationships listed here revolve around betrayal, either Castiel betraying the other (Anna Milton, Balthazar, Bartholomew) or the other betraying Castiel (God, Ishim, Metatron, Uriel).