Musubu Shiomi is a 2nd year junior high student with an ordinary life. At the seniors' graduation ceremony, she is approached by "Shizu-chan," her senpai and former childhood friend, who asks her to take a picture for him. "I'm going to Kitakou School...” ”I'll go to Kitakou too!"

Musubu is able to fulfill her promise made a year ago and successfully enrolls in the same high school as Shizu-chan, however....