The story takes place 2 years after the events of the TV series and follows Sonia as she continues to try to track down the "humanoid monsters". Her search takes her to a drug company called Draco Chemical, where she meets a man named Belum Eyesburg who looks exactly like Bem. Meanwhile, Belo continues fighting on his own in an effort to let Bela live as an ordinary human girl. After encountering Sonia, Belum begins having nightmares that make him question his own identity, and his peaceful, ordinary life with his wife and family begins to collapse...

(Source: Crunchyroll)

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