Sera enters into a secret three-year contractual marriage with Sebastian, the president of a conglomerate. Just as he is about to officially announce the marriage, she unexpectedly receives an ultimatum from her family. The initial warmth is gradually shattered by suspicion, scheming, and class prejudice. When she is humiliated and forced to leave, everyone is shocked to discover that this seemingly ordinary female consultant is actually the heiress of the top-tier Ashford family. A tangled web of love and hate thus begins.