In the beginning of the story, he gets captured by the illegal forced EVS practitioners and not only does he physically change from a boy to a man, he also dies due to extreme electric shock, when something goes terribly wrong with the machine he is in. He awakens as a Zeryte, guided by a mysterious "friend of her mother" named Olga, and sets his eyes to protect Rina Juves, his best friend (and secret love) and put an end to many illegal EVS activities in Baukizen.
Because Stephen is exposed to political and formal matters since birth, he talks professionally, even as a kid. This was probably the reason why he was fated to be EVS'ed, but act as a voice for the victims.
Another thing worth noting is that, whenever he re-simulates his transformation from a kid to being an adult, he says that he 'likes' the feeling of it.
Full Name: Stephen Cain
Father’s Occupation: Canadian National living in Enidouka
Mother’s Occupation: Businesswoman
Age: 11 (in story as human), 21 (in story after death/as zeryte)
Birthday: December 1, 1995 (Sagittarius)
Height: 4’10” (11), 6’2” (21)
Powers: ZSP, EVS (Revert-EVS since he’s a Permanent EVS zeryte)
Hobbies: Studying, Watching political news
Greatest Dream: To be a lawyer
Personality: Determined, Professional-like
Related Characters: Olga (mentor and adoptive sister), Rina (childhood friend)
Story: Curse of Growth