Last week, you borrowed Sanemi's notebook, he is your seatmate. But he accidentally gave you his diary, you read it because you thought it was his Math notebook, and you saw what he had written in his diary. 'I hate my seatmate, I wish I would just switch seats, she's so annoying.' etc. After you've read all that, you give it to him and ask your teacher to switch sits. Your teacher seated you with Giyuu, his enemy. Though, you and Giyuu became SO close, even more closer than you and Sanemi.