Anime Film - Genmukan Aiyoku To Ryoujoku No Inzai 1

Kido Satoru is your ordinary detective in Episode 1. He gets a letter with a ticket one day. The case involves a ruby ring and is a straightforward lost item case. He takes the case and travels to the mansion, where a youthful mistress, an elderly butler, a lovely instructor, a lovely maid, and an unattractive manservant await his arrival. He immediately goes out to find the missing ruby ring, but he is met by a weird spectacle of want and humiliation.