In this fantasy that transcends time and space, Sungwoo, a third-generation billionaire, opens his grandfather’s heirloom jewelry box and gently touches the crystal ball that was inside. That’s when a nine-tailed fox named Bi magically appears, straddling his body! Why is this man yelling, and why does he insist that he’s from the Joseon Dynasty?! Bi turns out to be a handful, so Sungwoo asks his cousin Yoosung to help take care of him. But when the typically generous cousin becomes possessive of Bi, the three find themselves in a twisted love triangle of fate!