Mizuha-chan is a normal high schooler who's in need of money. But seeing how at school she's a girl who's on her high horse most of the time and in her line of work she sometimes needs to ride living beings. Her "friend" Chapo, at the sight of how intertwined with the equine theme is her "friend's" fate, would tell you she is more of a jockey than a normal high schooler. Anyway, it was in one of those work shifts that our heroine got to know a certain 30 years old, virgin, "old man". Will he be just another stepping stone in Mizuha-chan's golden path? Or will her fate have a say in all of this?