Sine Cosine Love Sign

Hasumi Sawako's all girl's high school recently merged with the all boy's Kouryou High School and now, boys are milling everywhere. Among them, the most popular and handsome by far is the baseball team captain Sakuyama Yashiki, and one of the worst is his younger brother Wataru. Quickly, Sawako meets both of them, but under very different circumstances. What will become of these three?