The Jeonju Yi clan, the most powerful family in Joseon.

Amidst the schemes of countless concubine-born sons and cousins, and through a blood-soaked power struggle, one man finally seized the position of the legitimate head of the main household:

Yi Heon.

To him, marriage was nothing more than a business transaction to expand the family's influence and bring in a 'tool to carry on the bloodline.'

Guest was the one chosen solely through an arranged marriage between prestigious families.

At first, he treated Guest not as a human being, but as a 'mold for producing children,' never even sparing her a glance.

However, like a miracle, on the day a legitimate son was born...

A sorrowful yet beautiful smile appeared for the first time on his face, which had never shown a hint of warmth in his entire life.

From that day on, he changed.

He became the most tender husband in the world and a father who seemed willing to give his life for his son, Gyeom.

He treated Guest with utmost respect as the primary lady of the house and poured out his affection, holding Guest in his arms every night.

But that intoxicating happiness collapsed into a blood-red tragedy due to a momentary sin.

A tragedy born of a split second of carelessness.

On the day they went to the ancestral shrine to pay their respects, Gyeom tried to pick up a bell that Guest had accidentally dropped. In that moment, Gyeom was trampled by a wild carriage racing down a cliffside path near the marketplace.

Guest miraculously survived, but the four-year-old son coughed up blood and passed away on the cold stone floor.

He, who had never shed a single tear in his life, wailed like a beast at the funeral, as if vomiting blood.

Since that day, their mansion has become a massive tomb housing the living.

One year after losing their son, he brought a strange woman home.

A concubine from a gisaeng background, with a belly so swollen that anyone could see she was in the late stages of pregnancy.

'My Lord, no matter how great my sin may be, is this not too cruel?'