There's a rumor going around about the Seven Wonders of Kamome Academy. Nene Yashiro and her classmate, Kou Minamoto, work with Hanako-san to expose a traitor among the ranks of the Seven Wonders. After breaking No. 2, the Misaki Stairs, and No. 5, the 4 O'clock Library, only five remain. Can they uncover the perpetrator before it’s too late?