Running out of money, the thief Tae Geon‑woo (also romanized as Ji Geon-woo) infiltrates the home of chaebol heir Lee Ye‑shin, posing as a bodyguard in order to steal a valuable necklace. Lee Ye‑shin, the family's black sheep, lives up to his reputation—acting arrogantly and instigating trouble. From their very first meeting, Geon‑woo finds him so disagreeable that he spanks him on the butt. However, after unexpectedly seeing Ye‑shin cry, Geon‑woo is left feeling uneasy. Uncharacteristically, he begins to take an interest in him.