In the 4th year of the Great Yong Dynasty, Imperial Noble Consort Wynne Sullivan ordered the massacre of the East Sea fish tribe. The only surviving fish demon, Luna Lin, disguised herself as a young eunuch and infiltrated the imperial palace. She revealed her true form in the emperor's bath, won the favor of Henry, and was made Concubine Luna. She used a witchcraft case to strike back, causing the imperial noble consort's face to rot, and used the Imperial Grand Master to expose the truth that the imperial noble consort gave birth to a fish monster. After Wynne Sullivan was imprisoned in the Cold Palace, Luna Lin revealed her true form on a thunderstorm night to settle the blood debt, and Emperor Henry stabbed Wynne Sullivan through the throat. However, Luna Lin discovered that the real mastermind behind the tribe massacre order back then was Henry, the man beside her. She sacrificed her inner core to turn Henry into a fish and imprisoned him forever.
