Sick
This was actaully pretty sweet. Person A tries harassing person B to get a reaction from him. B obviously doesn't give a reaction, intrigues person A to the point where he pursues B. Really sweet A falls completely for B, B has a big family and A gets introduced into the family they all like him (except for the overprotective older brother). ~pretty good sex scenes
Kimi to no Dogfight
A goes to meet B for the first time in person (they met online) surprised to find out they go to school together. They develop their friendship, A catches feels for B but is unaware, B eventually catches feels and confesses to A. A is caught in a misunderstanding (thinks B is into his ex--childhood bestie, which he isn't)
Hinekure Sakura ni Koi ga Saku
Person A has big feels for Person B and follows him around and even to college. Person B initiates a relationship and overtime they develop real feels.
Introduction to the Theory of Love