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Tear Jerker: Nisekoi
In Shuu's crush arc, we realize that Shuu has a crush on Kyoko, the teacher, who is getting married in a month. Shuu decides not to do anything and just accept his heartbreak, spending the whole arc with a fake smile on his face. However, Raku points out that he's lying, he has regrets, and he should do what he wants to do instead of what's right, so he decides to run to her taxi and tell her his feelings for her. She tells him that she's glad he's not letting his youth go to waste, and that she wants him to be happy.
In chapter 115, The death of Ruri's great-grandfather. As well as Shuu helping Ruri, and Ruri being nice to him as a result.