Hester

Hester was an angel who was once part of Castiel's garrison. She and her colleague Inias were subordinate to Castiel, who was the garrison's captain before he rebelled against Heaven. She holds a profound disdain for both demons and the Winchester brothers, whom she blames for "corrupting" Castiel and the subsequent damage they've caused.

She appears in the Season 7 episode "Reading Is Fundamental" as part of a mission to retrieve Kevin, a newly designated Prophet charged with safeguarding the Word of God as according to the Heavenly Code, they must take him to the desert. She and Inias both appear at the mental institute where Castiel is being kept. When Sam and Meg try to stop them from taking Kevin, Hester instructs Inias to kill both the "demon whore" and her "lover". Before any fight can take place, however, Castiel interrupts. Hester and Inias are both stunned to see Castiel, as they believed him to be dead. Unfortunately, Castiel's erratic behavior (caused by absorbing Sam's madness, as well as his own guilt) convinces Hester that Castiel is insane. Just then Dean shows up and activates an Angel Banishing Sigil which banishes all the angels in the room.

After Meg kills two of Crowley's demonic minions, Hester and Inias are able to track the Winchesters and Kevin to their cabin in the woods. Once there they confront the Winchesters and Castiel again. Dean and Castiel both attempt to dissuade Hester from taking Kevin, as they need his help to stop the Leviathans. Hester, however, refuses to listen and tries to kill Dean. Castiel interferes and she turns on him and beats him up. When she draws an Angel Blade to kill him, Inias steps him and pleads with her not to kill Castiel, as there are already few angels left. Hester shoves him away and prepares to kill Castiel when Meg suddenly appears and stabs her from behind with her own Angel Blade, killing Hester and saving Castiel.