Synopsis
Koishikawa Miki is a perfectly normal high school girl. One day, her parents tell her they've decided to swap spouses with another couple they've recently met. The idea horrifies Miki, but she discovers that the other family has a boy her age named Yuu, and she falls for him. She relents, and the families move in together. Suddenly, Yuu's old girlfriend Suzuki Arimi shows up. Then Miki discovers that the boy she had a crush on in junior high, Suou Ginta, is in love with her! Ginta starts hanging out with Arimi, and it gets even more complicated from there.