Gin Hachi is the Ultimate Aetiologist. Aetiology is the study of the causation of disease.  His voice is medium pitched, soft, tired, and monotonous. 

Age : 16

Sex: Male

Details : 

Gin is very focused on his work, he devoted his entire life to his studies and often puts off sleep to continue his work. He doesn't really express much emotion, and keeps to himself most of the time, not really being a social person. He isn't an easy guy to crack, the only person knowing him being his grandmother whom he used to live with before the killing game. When put into high-pressure situations, Gin starts to nervously pick skin from his thumb. These situations usually include socialization of any kind, public speaking, and deadlines.