Ziyu, the flower of darkness in the 21st century, was buried in a sea of fire with her enemies after avenging her brother. But she didn't want to travel through time and become the princess of a subjugated country. He had already given up on living, but he met a man who looked exactly like his brother and was the prince of a subjugated country.
"In the last life, you died at the hands of others to protect my life. In this life, let me protect you."
However, while 'repaying' the family affection owed in the previous life, it seems that one is 'owed' the love in this life.