Sakai Kazuya is a 23-year-old man in love. Unfortunately, the object of his affection is a lovely woman only interested in well-educated men. So he enlists the help of her younger brother, Ezumi Masashi, to help him pass the high school entrance exam - but his services come with a very steep fee, and Ezumi isn't interested in money - he has his sights on some of Sakai's other assets!
I'm Not Your Steppin' Stone GN