Ichiro Kuga is a manga artist struggling to support his two young siblings, and he's in need of an assistant. Shiori Goshiki wishes to become that assistant, but her background is unusual in more ways than one.

Rainy weather complicates plans for Shiori and the Kugas. When Machi and Fumio are down in the dumps as a result, Ichiro and Shiori get creative in their efforts to make the most of the day's disappointing weather.

Shiori goes with the Kugas to visit their father's grave, as her relationship with Ichiro slowly deepens. When she comes down with a fever, it becomes Ichiro's turn to help her get back on her feet again.

The fated day arrives, the day when Ichiro and Shiori will annul their Engagement Pact. But there's a risk their feelings for each other will vanish in the process, and there's no way to be sure without performing the ceremony.