One rainy day, Kyunghoon runs into a crying man in the mountains who seems to need help, and puts him up at his place for the night. When the man wakes up, he introduces himself as a nine-tailed fox named Naroo and asks Kyunghoon to give him yang energy for the next 100 days so he can escape death.

For some reason, Kyunghoon can't bring himself to refuse Naroo's plea, and finds himself drawn more and more to the sweet and adorable fox the longer they live together. Strangely enough, the kind and gentle Kyunghoon reminds Naroo of someone precious from his past as well... could there be more to their coincidental connection than meets the eye?

(Source: Tappytoon)