Sakiomi is a student at Seiryou Gakuen, a girls’ school which just recently became co-ed. One day after final exams and before spring break, the school chairwoman suddenly gathered everyone together to announce that due to financial difficulties, the school will be shuttered and merged with its sister school, Shiraho Girls’ School. All the students had to move to the other town, and Sakiomi found himself surrounded by girls at a townhouse dormitory, including former student council president Sae, osananajimi Mio and imouto Tomoe.

Just before the start of the new school term, he unthinkingly walked towards the pool after attending the information session at his new school. He noticed a beautiful girl Sahori there, and it would be the beginning of a love story centered around him.