Jin Mitaka

Jin Mitaka (三鷹 仁) is the former resident of room 103. Jin is a third-year student of Suiko. He is Misaki Kamiigusa's childhood friend and a giant playboy. He has dated several girls, including Fuuka Kamiigusa, but in the end he breaks up with all of them.

He finally becomes a couple with Misaki during the fifth novel. He wants to become a playwright, and later attends a university in Osaka to achieve his goal. To pacify Misaki, he gives her a marriage registration form with his signature as a warranty, but Misaki ends up turning it in after his departure on the same day, which makes them officially married.

His residence in Osaka was revealed in Episode 24 to be in Utage-rin, Osaka Prefecture. This is a fictitious location.

Personality
Jin has a laid-back, caring but shy personality. He is able to guess directly other person's personality just by seeing how they work. He has feelings for Misaki, but he feels he is not good enough to match her, so he ended up becoming a playboy. He doesn't want to be swallowed up in Misaki's shadow, due to the gap that existed between them. Jin did confess to Misaki later on, but refused to go further because he still feels that he's not good enough.

Jin is creative with words. His scripts become the basis for Misaki's anime, and the both of then usually collaborate to make an anime. However, his scripts have been considered by critics, and even Misaki herself, as average. This is the reason that one, Jin kept on stalling his feelings and confession to Misaki, and two, why Jin moved to Osaka University of the Arts.

Relationships
Misaki Kamiigusa

Jin cares about Misaki a lot, and his concern for her influenced him in ways at certain issues at his life. An example is on why he applied to Suiko in the first place (so he can keep an eye on her). Even though Jin goes out with a lot of women, he always has Misaki in mind, however, he somehow feels obligated to do this for two reasons. One, Jin doesn't feel that he's good enough for her, which is a recurring theme, and two, because he somewhat feels jealous about her successes, and wants to see Misaki get crushed.

Nonetheless, Jin is capable of keeping up with Misaki's tirades, even if he himself gets annoyed at times.

Sorata Kanda

Jin and Sorata are the best buds in the dormitory, and often talk about things they don't want to tell to their significant others. Jin holds Sorata as a trusted friend, opening up issues relating to Misaki and other things he is otherwise unable to tell her himself.