Kitou Kaki

"Are you prepared to die? Or do you wish for agony even worse than that?"

Appears 18 years old, actual age 92 years.
The strongest oni who takes up the name of the 'Onigashira' and acts as their leader.
The student council president at Onigasato High School, he's unsociable and doesn't talk much.
Even though the protagonist is supposed to be his bride, for some reason he feels a strong killing intent towards her.