He is the lead vocalist for Zero Sum Game and a friend of Yazaki.
Keito is created by Hatsuki Kyo. He has no information regarding any inspiration used to create him. Keito first appears in volume 1 of Cross and Crime.
He is seen singing to the audience, and afterwards, he gets a text message from Yazaki Norikazu who wants to interview him for his newspaper and to hang out. He looks forward to his meeting his long time friend. In his meeting with Yazaki, he meets Tokano Yuuka (Yazaki's girlfriend) and sighs a bit. During his good time with Yazaki, Yuuka objects to getting her boyfriend more drunk. Instead, he offers Yuuka a drink. Later, Keito is accompanying Yazaki as he recovers from the alcohol while he knows what happens to Yuuka who is being raped at the studio.
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