Haruki Mishima and Towa Honda are new students at Aokisora High School and best friends; at a convenience store near their high school, Haruki runs into his classmate Miharu Mashiki, a girl he's recognized since he was little.

Disgusted by the irresponsible and talkative Towa, serious class representative Mami has been avoiding him; even when Mami begins avoiding him even more after a certain incident at the convenience store, Towa is undeterred.

Towa and Mami are steadily growing closer, but they both have concerns about their families; Towa is having trouble with his relationship with his mother, and Mami remains unable to tell her family about her relationship with Towa.