At the Palace of Yeomra in the afterworld, Jae-shin, the enchantingly beautiful yet deeply hedonistic son of the king, faces dire punishment. Having tampered with two men's lifespans, this alluring half-human, half-ghost is banished to the mortal world, where in daylight, he is stripped of his power and appears as a mere white puppy. The only way to return to his true form is to win over the heart of a human. As if by fate, Lee Nok, a wistful and unfortunate prince pining for his childhood friend, takes pity on the animal and brings it in. While Nok's abundance of yin energy attracts malevolent spirits, Jae-shin must absorb yin to sustain himself. In every respect, Nok is the perfect target for Jae-shin's goals. He begins visiting the prince's chambers at night in his human form, hoping to erase the traces of affection for another from the prince's heart and lure him into eternal love. [Written by MAL Rewrite]