Because of her family's poverty Yata, a high school student, was searching for a really cheap lodging. And she found it in a certain shared-house type apartment. Each of the residents of which happened to be, surprise-surprise, some kind of demon (with big mammaries also)! And so the story of a bit lewd, sometimes bizarre and often noisy cohabitation of Yata and others at human world, receiving those big-breasted demon-girls trying to fit in, is getting started!