Moto Kano-sensei wa, Choppiri Ecchi na Katei Houmon de Kimi to no Ai wo Haguku Mitai.

A high school boy, Toruma Nijino, who has suffered a series of heartbreaks, welcomes a new school year, and the new teachers are his ex-girlfriends who dumped him! The two, who are still in love with him, meet at his house. They get him to promise that he'll treat them like teachers until he gradua...

Source: MyAnimeList