In her previous life, she was a world-famous killer, fighting in wealthy families during the day and rolling on the tip of a knife at night. He is a domineering "rich second generation" who deeply admires her and wants to get her day and night. A contract marriage bound them together.
He is her adopted brother, who has protected her since she was a child. Although he knows that the killer needs to end his love, he still misses her and stays with her silently.
He is her brother-in-law, and he is often at odds with her on both sides of the aisle. Using each other, they unknowingly became understanding and relying on each other.
He was a fellow traveler who met by chance. For her, she was willing to give everything. She just didn't know whether it would be fate or not.
The fate that was determined thousands of years ago has never changed?
The story of thousands of years ago, under the leadership of Sanshi, is repeated in the 21st century. But, is the ending still that poignant?
In the arena, who wins and who loses? In love, who wins and who loses...