From Viz:
The Prettiest Boy in School isn't A Boy! Japanese-American track-and-field star Mizuki has transferred to a high school in Japan but not just any school. To be close to her idol, high jumper Izumi Sano, she's going to an all-boys' high school and disguising herself as a boy. But as fate would have it, they're more than classmates. They're roommates! Now, Mizuki must keep her secret in the classroom, the locker room, and her own bedroom. And her classmates and the school nurse must cope with a new transfer student who may make them question their own orientation.

Contains the one-shot Wild Kiss.
The story follows a student named Tomoki Asakawa and a mysterious boy named Chihiro Yoshida.