Kazahaya is rescued from freezing to death on the streets of Tokyo by another young man his age named Rikuou. Now Kazahaya rooms with him (who he dislikes for his attitude, even though he's grateful to him for saving his life) above the drug store they both work at, Green Drug. Both work for the mysterious store owner Kakei, while putting up with Kakei's "friend" Saiga, who is always teasing them. The strangest thing about Kazahaya's job is that he and Rikuou are often sent on "extra jobs" by Kakei ...which are different and stranger every time, be it to retrieve a book or a girls' school uniform. Kazahaya always accepts the "extra jobs" so he won't end up without money and on the streets again...but he really wonders what the purposes are of these "extra jobs".