Sekai wa Bokura no Tame ni!

Synopsis

Ogawa Maho is a young, fresh teacher who just arrived in Tokyo to take on a new teaching position at a high school there. Things don’t go as she planned, however, when she breaks up with her boyfriend whom she had been dating for 6 years. Distraught over her breakup, Maho has a one-night stand with a guy she meets on the street. The encounter was memorable and manages to cheer Maho up enough that she can face her new job and move on with her life. Of course she is shocked when she discovers that the random guy she spent the night with happens to be one of the students in her new class! (Source: shoujo-manga)