Kanojo wa Hanayome Kouhosei? - Season 1

An orphan named Shinji is approached by a maid called Zero, who informs him that his late father was the sole heir to a wealthy family. His grandfather now demands that Shinji assume control of the family business. Shinji, however, has no interest in this inheritance and wishes instead to pursue a life with his childhood friend, Sae. His grandfather provides a single condition for refusal: Shinji must locate a woman bearing a specific birthmark. This mark, however, only becomes visible after she experiences sexual climax. Shinji must navigate this stipulation while remaining faithful to his existing relationship.