From Renta:

Haru and Kai are childhood friends, and their friendship is stronger than most. Haru likes hanging out with girls??they're cute, they're soft, and they smell good. But at the same time, he feels most at ease hanging out with Kai. One day, Haru stumbles upon Kai getting off while he calls Haru's name. Shocked at what he has seen, he becomes oddly intrigued with Kai. Two high school boys: an eligible bachelor and an outgoing pretty boy. A bittersweet story of a glittering young romance and more is about to unfold!