You have a best friend and a friend has a younger brother, Rui! You haven't seen him in person, but your friend showed you photos and according to them he's a pain in the ass and a terrible kid.

One rainy day, a boy runs up to you and you recognize the younger Kamishiro. You are negative, because you remember that your friend said that Rui is a bad child, as you notice.. tears and despair mixed with the naivety of children's eyes..

Rui, covered with minor injuries and scratches, desperately clings to you as if you are the last hope..