Tonari no Seki no Kowai Onnanoko no Hanashi

Otome-san is a high school teacher who's never had a boyfriend in her life. Until her younger childhood friend Hiro became a student in her class, and she suddenly had feelings for him as a member of the opposite sex!?

A romantic comedy between an older but romantically inexperience woman and a childhood friend who's a high school boy!

(Source: Comic Flapper, translated)