|“||I hate my family. (...) I'm not like them, I promise.||”|
— Cyrus Frankenstein
in The Prisoner
Cyrus Frankenstein was an unusual member of the Styne Family.
Cyrus was born to Monroe Frankenstein and was the younger brother of Jacob Styne and Eldon Frankenstein. Unlike the rest of his family, Cyrus was not evil and had no surgical enhancements, seeming to be more of a geek. Cyrus secretly hated the Styne's and wanted to leave when he could but was afraid they would kill him.
In 2015, Cyrus was bullied as he left school, but made fun of the bully rather than being scared. While he lied to his cousin Eli about what happened, Eli later kidnapped the boy for revenge and dissection. Eli interrupted Cyrus while he played video games and showed him their captive. Monroe insisted Cyrus kill the boy or he would do it himself in a more brutal way, then dissect Cyrus. Cyrus reluctantly did so, looking away the whole time and cried afterwards as the boy's arm was used to replace Eldon's ripped off one. Monroe decided to have Eldon and Roscoe raid the Men of Letters bunker and Eldon decided to take Cyrus along. While Eldon and Roscoe trashed the bunker, Cyrus looked through the books which he found interesting and found a picture of Bobby Singer with Sam and Dean and tried to keep his brother from burning the books they couldn't take and Sam and Dean's things to no avail. However, before Eldon could set everything on fire, Dean killed Roscoe and confronted Eldon.
Cyrus was stunned to hear that his family was dead, having been slaughtered by Dean before he watched as Dean killed Eldon and turned his sights on him. Cyrus quickly insisted he wasn't like his family, showing Dean how he had no surgical enhancements and telling him he hated them and didn't want to be like them. Dean insisted that evil was in Cyrus' blood and after appearing to change his mind, shoots Cyrus in the head, killing him. Castiel later examines Cyrus' body, shocked at the brutality of Dean's actions as in the past he would've spared Cyrus.
Unlike the rest of his family, Cyrus was not a cold-blooded monster and hated his family and their ways. Cyrus was shown to be afraid of what his family would do to him if they learned he wanted to leave and what his father would do to him if he didn't murder someone. While Cyrus reluctantly killed the boy, he was barely able to look as he did so and was in tears following the murder. While Cyrus showed willingness to stand up for himself to bullies, he was terrified in the face of death shown when threatened by Dean.
In contrast to the rest of his family, Cyrus showed a great degree of compassion, obviously upset about his tormentor's predicament even before he was forced to kill the boy and trying to convince his brother not to destroy the Winchesters things unnecessarily. Cyrus also gave a fond smile to a picture of the Winchesters and Bobby Singer and hid the picture in an attempt to protect it. Cyrus had an obvious thirst for knowledge as shown when he was more interested in reading the books in the Men of Letters bunker library rather than collecting or destroying them.
- He loves playing Dying Light, a zombie video game.