Lin Ziyan was born into a wealthy family in the 21st century. But as the second son born to the primary wife, he had to keep a low profile and act like a playboy just to survive. Then an accident allowed him to transmigrate to the Tang Dynasty with a System, where he became the eldest legitimate son of the orthodox Lin family of Xuzhou, descendants of Bigan. In this life, he no longer has to hide his intelligence or abilities. See how Lin Ziyan changes the course of the Tang Dynasty this time around.
P.S. The male lead is in a straight romance, one-on-one, with an emphasis on court politics.