Kyousuke is in a one sided love with his childhood friend, Kasumi, who is dating a women who is already in another relationship. Kasumi did confess in the past but was rejected by Kyousuke since he wants Kasumi to have a normal life filled with happiness, even if he has to make his life unhappy.
When Sougo was a child, his childhood friend, Shiro proposed to him but he turned him down since men can't marry. Years later, Sougo took it as a cute memory but Shiro took it as a goal and became prime minister, changed the same sex marriage law and proposed to Sougo once again.
Tanaka and Koniu are coworkers and have been friends for the past 10 years since they became friends in high school. Tanaka is the caring type so he have always helped Koiinu when he needed it. After a night of drinking, Koiinu wakes up naked next to Tanaka with no memory of the previous night.
Since Kiryuu Yoshitsugu have been a child he have been by Kaede Saoinji's side since Kiryuu's family have served the Saoinji family as butlers for generations. Kaede loves reading shoujo manga with his sister and dreams of finding his prince like in the mangas. However, Kiryuu will never be able to be Kaede's prince due to their social standings but he will settle to be his knight instead.
Tamaki and Shunta have been together since they were brats and during elementary school Shunta's feelings began to change towards Tamaki. Although they are 1 year apart, they are still friends during their high school time.
Childhood friends, Ryou and Yuu, started drifting away from another when Ryou slept with Yuu's girlfriend when they were still young and instead of giving a reason, Ryou ended up leaving japan without talking to Yuu. However, upon returning to Japan and attending a university, Ryou ended up going to the same Uni as Yuu but even after years of sepperation, Ryou refuses to become friends nor wants to meet Yuu.
Haruomi (Dancer family) and Soutaru (young master) knew each other as children but they fought and right after, Soutaru went with his father to Germany for 9 years. Soutaru came back to Japan and want to see Haruomi once again, hoping that Haruomi does not hate him from the awful things he said, However due to mistaken identity, Satarou end up working as a servant at Haruomi's place.
Onoda is the popular guy in school who is always around girls while Hiroto is his childhood friend who does not stand out from the crowd. After starting high school, Onada and Hiroto stopped talking or interacting with one another for reasons unknown to Hiroto.
A story where a childhood confession scared both boys. The one who confessed ended up moving while the other one could not bear the guilt of making his friend cry. As fate has it, they not only ended up in the same distant high school but also as roomates.
Kimi ni Ienai Koto ga Aru