大広間の壁に現れた『死んでつぐなえ』の文字。メッセージの意味と、その犯人を巡って話し合う紘美（武田玲奈）たち。すると、水谷和希（松本享恭）が浅見ルナ（上野優華）に送った告白メールがいたずらでクラス中に拡散された事件に思い当たる。この場にいない水谷が黒幕なのか？しかし、非情にも投票の時間は迫っていた…。
The words "Die and become one of us" appear on the wall of the hall. Hiromi and the others discuss the meaning of the message and the culprit. Then they think of an incident in which a confession e-mail sent by Mizutani Kazuki to Runa Asami was spread throughout the class as a prank. Is Kazuki, who is not present here, the mastermind behind this? However, the time for voting is ruthlessly approaching...
