Around the same time of Shizuka's return from France, Tsukushi's elementary school friend, Kazuya Aoike, transfers to Eitoku. Tsukasa becomes jealous of Kazuya and gives him a red slip. Eitoku's students begin bullying the two severely until Rui steps in to protect Tsukushi.

Concerned for Rui, Tsukushi begs Shizuka to stay in Japan. Shizuka clearly explains her reasons for leaving. Rui overhears the conversation and becomes angry. After Shizuka leaves, Tsukushi yells at Rui to follow her. He reveals that he was already planning to.

After seeing Tsukasa with Sakurako, Tsukushi meets his sister Tsubaki Domyoji, who brings her to their house. Tsukushi manages to hide but gets lost in the huge mansion. He comes across her and becomes angry when she mentions Rui's name. Tsubaki comes to her rescue in time.

Tsukasa invites Tsukushi to his birthday party. Before entering the party, Sojiro reveals that Tsukasa's mother, Kaede, will judge her as a potential fiancée. Tsukushi becomes nervous and attempts to leave, but ends up staying. She accidentally causes a scene before meeting Kaede.