Loen Setia was the long-time lover of the emperor, Cassis Albinese, but was reduced to a mistress because of her status. In the end, Loen met her cruel death at the hands of the jealous Empress and Cassis, who had a change of heart… Before she knew it, she had been reincarnated on the day she entered the palace as Cassis’s mistress. Although Loen is confused by her incredible situation, he is grateful for the opportunity she has been given and vows to take revenge on Cassis, who betrayed him, and her Empress’s gang, who caused his death. One day, Loen faces a shocking truth in a corner of her imperial palace. When Loen learns of the contents of her former emperor’s will, which appoints her as her next empress, Loen trembles with her chagrin and becomes furious. Meanwhile, Cassis becomes more and more attracted to Loen, whose attitude is different from hers before. When she returns to her life, Rowen learns her terrible secret, and will he be able to successfully take revenge on her and regain his place…?