Returning home, Iori switches bodies with Aoki and is amazed by how tall he is. Yui takes the opportunity to ask Iori why she lives alone and is horrified to learn Iori is completely unconcerned about household intruders.
A week later, everyone meets at Inaba's house where Yui and the others confess to having failed to obey their rules, much to Inaba's frustration. Realizing how hopeless their situation is, the group decide to establish rules to ensure no one else learns of the bizarre phenomenon and so they can continue living as normally as possible. She and the rest of the club can only watch as Heartseed takes his leave. After a defiant Inaba is shoved away by Heartseed, Yui attacks her mysterious tormentor but he effortlessly blocks all of her strikes before tossing her to the ground. Heartseed reveals that he is behind the phenomenon and that the Cultural members will continue switching bodies at random until he is sufficiently entertained. Who takes control of their club advisor, Gotou to speak with them. Later, Yui and the rest of the club encounter the mysterious Heartseed The following day, to Yui's distress, she is once again swapped into Aoki's body and spends much of the morning waiting with the others for the switch to wear off. After Taichi and Iori swap bodies, however, Yui and the others are convinced of the phenomenon.
However, the rest of the Cultural Research Club are reluctant to believe their story and Yui begins to have her own doubts. The next day, Yui and Aoki discover that they experienced the same bizarre phenomenon and decide to inform their friends. Horrified, Yui hides under the bed sheets only to suddenly find herself back in her own room and body. Upon inspecting her new environment, Yui realizes she is not only in the room of her abhorrent admirer, Aoki, she's in his body. On a night that should have been like any other, Yui awakens to find herself in an unfamiliar room.