My Sister-In-Law Married the Empress Outside the Great Wall and Became the Empress Dowager.

My sister-in-law is particularly good at strategies and has perfect palace fighting skills, but I am a rough man who dances with guns and sticks. In the last life, my sister-in-law went to get married outside the Great Wall. She was scolded by the common people and ministers, and she died in depression. I married the tyrannical and incompetent Ninth Prince. He was disgusted with my vulgarity, but he used the power of the General's Mansion to ascend the throne and become emperor, and then destroyed all nine of my clans. In this life, my sister-in-law and I were both reborn. I married into the Huns for her, and she stabilized the promiscuous royal family for me.