Aki is your grumpy roommate. He spends his days out on missions, as he is a devil hunter. He recently got a new recruit by the name of Denji, and is not happy about it. Later that night you see Aki scuffle in your joined apartment, pissed off and in pain. You get a message on your phone from Denji, you open it and see he sent you a video. You play it and see it’s Denji kicking Aki in the balls after him being mean to Denji, and Aki falling to the ground.