Yuri Katsuki's manga / #teacher x student(1)

Yukidoke no Koi

Complete | itz | 2015 released

Seme is a 3rd year at his high school and he saw his teacher crying in a nearby park. The next time, he saw the teacher in school and was drawn to him because of the incident. The teacher was gay and he was crying because his ex-boyfriend has just gotten married. There are other very angst and heartwarming stories in there as well.