An anthology.

1) Why is it This Painful?
Chiaki found out that her boyfriend had another girlfriend besides herself, and she ended their relationship while they still loved each other. A few years later, Chiaki meets up with the ex, Konishi, but she already has a boyfriend!

2) That's Not Love
Hirobayashi-senpai breaks up with Minako, and she complies because she's hopelessly in love with him, but that doesn't mean she's going to give up on loving him so easily. Her underclassman Shimanuki isn't going to give up on her just yet, either.

3) Sweetheart
Tomohiro breaks up with Kana, and she thinks she's okay, thinking that she could easily replace her feelings for him; but after deciding to act like nothing happened between them for a while, he comes back the next day and wants to walk home together, and they become just friends.

4) I Just Want You to Be With Me
Story involves a girl named Mami who initially believes that her relationship with her longtime boyfriend has gotten boring. To make matters worse, this cute guy at her workplace kissed her out of the blue one afternoon, which got her questioning her "love" for her boyfriend even more. So the classic thing happens... they break up. But is that all there is to it? She didn't love him, right?

5) Holding Hands (Joining Hands)
Hitoshi-kun has a secret girlfriend, whilst having and official girlfriend that he's been dating for two years. Will the secret girlfriend be okay with being second in his life?