One morning, as she left for work, she found a dragon before her. Stunned, the dragon transformed into a beautiful girl with horns, a tail, and a maid outfit right before Miss Kobayashi's eyes. Calling herself Tohru, this dragon-girl asked, "Please let me serve as your maid from now on!" Confused by her question, Miss Kobayashi remembered inviting the dragon into her home last night while drunk. She refuses, saying she can't afford to hire someone, but then she realizes she's almost late for work and--

Miss Kobayashi was growing accustomed to her new life with Tohru, and so they headed out to go shopping together. She's surprised by Tohru's social skills though, when she sees how friendly Tohru was with the people of the shopping district. However, Tohru herself makes the dark claim that she's only pretending to be friendly, and shows how she still doesn't understand human emotions. Then on one of her days off, someone calls at Miss Kobayashi's home. She opens the door to find a little girl with horns and a tail--?!

Kanna starts living with Tohru and Miss Kobayashi. While the livelier residence is nice, sharing a tiny apartment with three people becomes cramped. So Miss Kobayashi decides to move. She winds up inviting Takiya to her new apartment for a party, but Tohru also invites her dragon friends, Fafnir, who lives in a cave, and Lucoa, who's lived in this world since ancient times, to visit their new home.

Kanna is invited to Saikawa's home. Since Saikawa's family has a maid too, they invite Miss Kobayashi and Tohru to join her. When a genuine maid, Josie, greets them, Miss Kobayashi gets excited. The two hit it off, chatting about maids. To top things off, Lucoa announces she's planning to live in this world too. She claims she was summoned by Shouta, a member of a mage family. Lucoa gets very touchy to try and get along with Shouta, but she goes overboard...

Miss Kobayashi and the others go to the beach. But Lucoa's immediately dragged off by one of the lifeguards for her overly skimpy swimsuit. After regrouping, they put sunscreen on each other, split a watermelon, go swimming together, and enjoy summer to the fullest. After the beach, it's comiket! Tohru and Miss Kobayashi both head for the otaku's battlefield, and even Tohru gets shivers from the incredible aura surrounding those otaku. While helping Takiya with his circle, Tohru's horns and wings are mistaken as cosplay?!

It's winter and Christmas is coming soon when Tohru is asked to put on a performance for the old folk's home. Tohru and the others decide to put on a play so as to not bother Miss Kobayashi while she's busy, yet without her there to control things, the play the dragons devise takes an unexpected turn... Finally, the play is put on, and while Miss Kobayashi watches their performance with anxiety...

Their day off is peaceful, and Miss Kobayashi spends her time relaxing with the others as usual. However, while out shopping, Tohru suddenly stops to think on the street--Miss Kobayashi is human, and what will she do when her lifespan runs out and she dies...? They can't be together forever. They'll have to part someday. She knew that. She was prepared for that. Yet still, Tohru's mind is in turmoil, and the final blow is dealt when the Emperor of Demise--her father--appears before her.