>the Christmas chapter
A week before Christmas, Yukimura asks Kodaka if he could spend Christmas Eve with her. Kodaka apologizes and says he already has plans (Christmas party with the club) because he had thought she'd be busy with the student council party. Yukimura asks him if he could cancel it, but he says he had already promised Kobato and Maria. Yukimura then says they should have sex on Christmas Eve. Kodaka is taken aback but is excited. However Yukimura shocks him by saying "otherwise, let's break up". Kodaka says breaking up over not spending Christmas with her is too extreme.
Yukimura says that she has come to the conclusion that she can't make him truly happy. Kodaka says he is happy when he's with her, but she says he is happier when he's with the club. Kodaka can't refute her. She tells him that time is limited and though she's happy that he has taken the time to be with her, there are only 3 months left until the end of high school and his time with the club. Yukimura asks him to choose. If he decided to spend the Eve with her, they will have sex and the next morning she will put her life on the line to make him happy, otherwise they will break up.
Kodaka says he needs to think about it. In his mind, he knows choosing Yukimura is the right thing to do, but her "time is limited" and "there are only 3 months left" continue to echo in his head.
Then comes the Christmas party. Yozora says she has one more present for everyone after they finish exchanging their presents. The present turns out to be Yukimura. Yozora says that Yukimura got dumped by her boyfriend 3 days before Christmas Eve and is more unfortunate than everyone else in the club. Yozora then says no one would be again a super ultra non-normalfag like Yukimura joining the club. Everyone welcomes Yukimura back with a round of applause. Yozora asks Yukimura to do the greeting upon joining the club, and Yukimura screams "go to hell normalfaaaaags!".