Disregarding Shinoa’s warnings, Yūichirō grabs the possessed axe. He is immediately pulled into a vivid hallucination of his dead orphanage family, where a demon masquerading as Mikaela tries to manipulate his desire for revenge.

Shinoa Hīragi takes Yūichirō and Yoichi Saotome to a restricted area beneath the school to demonstrate the dangers of "Cursed Gear". They find a student who has been possessed by a demon after failing to control a powerful weapon.

The episode concludes with a major reveal in the vampire city, Sanguinem. It is confirmed that Mikaela Hyakuya is still alive , having survived the massacre years ago and been turned into a vampire. Key Characters in This Episode

Acts as a mentor and guide, revealing that the school is actually a training ground for the Moon Demon Company.

Yūichirō realizes the illusion is fake because the "Mika" he sees is acting out of character. Through sheer willpower, he expels the demon and wakes up, proving he has the strength of heart required to wield Cursed Gear.

Shown as a vampire soldier, marking his return to the story after the time skip. The Demon in Your Heart (Episode) | Owari no Seraph Wiki