After losing her parents, Peony prepares for a life in a convent until the king unexpectedly sweeps her away to be his mistress. Strangely resembling her first love, Zack, the king's demeanor is starkly different, leaving Peony discontent. However, a revelation unfolds as the king confesses to truly being Zack, reigniting their passionate connection. Yet, beneath his loving facade lies a secret agenda, hinting at a king determined to fulfill his forbidden love at any cost.