Happiness!

Haruhi Kamisaka is one of the mages in training at Mizuhosaka Academy who on Valentine's Day, runs into Yūma Kohinata, who she believes may be a boy she's been trying to find for years. After the magic section of the academy suffers from a gas explosion, Haruhi and her friends transfer over to the normal section and Haruhi ends up in Yūma's class.

A new school year has begun and the upperclassmen prepare for the entrance ceremony. Of the new students, Sumomo, Yūma's sister, is entering as a first year student. Later, Haruhi and Anri are invited by Yūma and his friends to participate in the cherry blossom viewing with them occurring the following Sunday.

The students aren't coming to the school cafeteria as often as they used to and Anri begins working as a waitress in order to bring in business. However, complications arise.