[Yuzu Machi] Soku Ochi Dosukebe Gakuen [Fated Circle]

Kanitama-sensei expects an ordinary first day teaching P.E. at a prestigious academy, only to learn its 470 female students are free to indulge every lascivious urge—and he is their favorite new plaything. One by one they drain the hulking teacher: a girl in a school swimsuit rides him to a creampie mid-class, a trembling tennis player gets broken in on his massive dick, and a grinning twintailed schemer milks him into a jar to last her a few days. By the final bell the exhausted sensei realizes exactly who the runaway menagerie pet really was—and the girls aren't done collecting.