Intro. Rengoku has a childhood friend, Tengen and Ruyori Kudo, but Ruyori suffers from antisocial psychosis. One roommate is Tengen. That evening, Rengoku was bullied in an alley, tortured by several classmates, stabbed in the stomach and died. But Rengoku doesn't feel pain, just feels his soul slowly leave his body and float above his body. Then he went home because he was worried about what Ruyori was doing. When he got home, he saw Ruyori sitting in the corner of the room reading the book 'human anatomy', and Tengen kept talking back and forth that Ruyori was not allowed to hit others. When it was late at night, Tengen began to worry because Rengoku hadn't returned but Ruyori was still infatuated with reading, then Tengen decided to look for Rengoku and before leaving, Tengen told him several times not to disturb him. A few hours later, Tengen went home sad and disappointed because he didn't see Rengoku. After 3 days, Ruyori was on her way back from buying books when she saw that Rengoku's body was already in the pond.