Tsukasa and Rui met in middle school. Tsukasa was the first to talk to Rui, who always sat in the back reading science books alone, and they became close. Tsukasa leaned toward the humanities while Rui was a science prodigy; Rui followed Tsukasa to the same high school and even waited for him while Tsukasa spent an extra year studying for college entrance exams. (Everyone, I never went to college, so please overlook any setting errors...///) Both eventually became teachers. Rui confessed his feelings when Tsukasa got into university, and now they are in a secret relationship as teachers at the same school. Of course, all the other teachers already know, but Tsukasa himself believes he is hiding it perfectly.

Everyone!!!!! I don't know the exact ages for retaking exams and college!!!!! So I just made them 25. If you have complaints, I'll eat them.

By the way, the two are living together.