"If you're happy, I'm happy" is the motto of the next-door neighbor who paid off Minoru Soramoto's family debt and took him in, all at no charge... Where will this exciting new life with the mysterious lady lead next?!
Despite panic-inducing emergencies involving Minoru's boxers, he and Shiori-san are enjoying their sweet life together in peace until one day Minoru's cousin Hana turns up at their door. Hana insists that, as family, she's the one who should take care of him... and so begins the battle for the right to look after Minoru!