Kobayashi lives alone in an apartment, until one day, Tohru appeared and they ended up living together. Tooru looks down on humans as inferior and foolish, but having been saved by Kobayashi-san, she does everything she can to repay the debt and help her with various things, although not everything goes according to plan. A mythical everyday life comedy about a hard working office lady living with a dragon girl.

As Kobayashi sets off for another day at work, she opens her apartment door only to be met by an unusually frightening sight—the head of a dragon, staring at her from across the balcony. The dragon immediately transforms into a cute, busty, and energetic young girl dressed in a maid outfit, introducing herself as Tooru.