Tomohisa is a teenage boy. He has short black hair and hazel eyes. He wears the Minazuki Academy High School uniform, consisting of an open-necked black shirt with lavender cravat underneath, a white blazer, black pants, and pale brown shoes.
Tomohisa is the heir of a powerful monopolistic organization and is somewhat recognized by the upper-class community. Although Tomohisa serves as the vice class representative of his classroom, no one seems to listen to a word he says. This is in stark contrast to the head class representative, Curara Teshimizu, who can instantly calm the class down. He holds a secret jealousy and rivalry in his heart toward her for this reason. 
Tomohisa is only shown briefly as he escaped from the monster that was attacking Ryuji Shimazaki and Curara in the operating room. He bumps into Ayame Itou and Ritsuko Satomi along the way, and runs away screaming. He is later shown to be captured by the SWAT team alongside Chiyomi Homura.
Significant plot details end here.
Tomohisa's nickname is a pun of Shiba Inu, a Japanese dog breed.