The story follows a hikikomori (shut-in) named Sasami who is unmotivated about even changing clothes or eating. Her brother takes care of her, even though she despises his slave-like nature. Sasami spends her days viewing the outside world via a "Brother Surveillance Tool" on her computer. In the outside world, the three beautiful Yagami sisters and Sasami's brother are in the middle of relationships worthy of a romantic comedy.