Running low on creativity, Chihiro Sakai, a novelist, visits a pet store to ease her stress. To her disappointment, she discovers her affection for cats triggers her allergies. To her surprise, a stranger at the store volunteers to serve as her "pet" instead. Chihiro, delirious from exhaustion, accepts the offer, and they proceed to her apartment. After dozing off, Chihiro awakens to a freshly cleaned home and a delicious meal courtesy of Nagisa Wataya - the lively and stunning "pet" she had taken in. But little did she know, Nagisa had quite the peculiar personality...
