HUNTC-500 Trace from the body, who did it?

HUNTC-500 Traces from the Body, Who Did It, A Synopsis, A Story in a Classroom with a Complicated History. When a male student in the room lost his first loss without him knowing it. But now he has another male student friend to help. The two of them begin to investigate the truth about what happened to him. Sera , Haru Kikuchi , Wakana Yamori and Nishio Marina are the suspects