Yeon, a nine-tailed fox who despises humans, avoids an accident with the help of Dong-i, who happens to be a human. In essence, a nine-tailed fox is a being that must repay a favor it receives. Yeon visits Dong-i without missing a day in order to repay the favour. But Dong-i feels burdened by her kindness. The two, who seemed like they could never become closer, become aware of each other's wounds and shortcomings, fill them in, and feelings emerge within their hearts. With different backgrounds, species, and even ways of loving, can the love between a Gumiho and a human truly end happily?