Great Tang: I Shared Pingyang’s Bed and Became Taizong’s Brother-in-Law

[Transmigration + no System + living off his wife while standing his ground + daily life + romantic rivalry]

Chen Xian transmigrates into the body of a tenant farmer on Princess Pingyang Li Xiuning's estate. He is summoned to attend to Li Xiuning in bed, but after she gets dressed, she refuses to acknowledge him. Chen Xian can only fight back, and a clash breaks out. In this prosperous Tang Dynasty, Chen Xian plans to serve Li Xiuning well and enjoy a peaceful country life. Unfortunately, one problem after another comes his way. He has to help Li Shimin deal with troublesome matters, suppress the Turks, destroy Tuyuhun, develop the Western Regions, and bring the surrounding tribes under the empire's rule.