Retired Soldier Works as a Security Guard on Campus

King of Soldiers, Invincible, City

Qiu, the male protagonist was framed by the four major families and ran away. Five years later, he became the king of soldiers. The heroine wrote a letter to the hero, begging him to come back and help her protect the heroine's sister, and the heroine was forced to jump into the river. I can't find it. Please, I don't know the title of the book🙏🙏🙏