牛島がニーナに会いに来た真意を探ろうと、厚志とマサは意を決して牛島の家に向かう。ドタバタの末に牛島家を飛び出す厚志とマサ。その後、厚志はニーナと会い、マサは麻美にメールを送った。ある日、厚志の前に牛島の弟だと名乗る男の子が現れた。牛島弟の雅と一緒にニーナの待つカフェへと向かう厚志。性善説を訴える雅にマジ切れしたニーナに厚志は・・・。
Atsushi and Masa head to the Ushijimas' house to find out the real reason why Ushijima came to see Nina. After a slap in the face, Atsushi and Masa run out of the Ushijima's house. Later, Atsushi meets with Nina and Masa sends a text message to Asami. One day, a boy who claims to be Ushijima's younger brother appears before Atsushi. Atsushi and Ushijima's younger brother, Masa, head to a cafe where Nina is waiting for them. When Nina snaps at his good-natured theory of sexuality, What will happen to Atsushi...?
