Otohiko Zaizen is Ayane Tanise's boyfriend and one of the victim in Human-Eater Laboratory Murder Case.
Appearance[]
Personality[]
He seems to have a good relationship with Tanise, and although he is full of curiosity, he lacks a sense of tension. In the middle of the story, he makes a deal with the real criminal, but after that he is found dead after supposedly hanging himself from the doorknob in the basement.