SSS Rank Dragon Tamer: Unleashed - Chapter 13

For the sake of the world, the Protagonist must die.“I... I think I like--”Whether you’re just a girl who fell in love with the wrong person.“N-no...! If I can go back... just one more time...!”A man who regresses to save the world.“Hero... Please, kill yourself.”Or a destined Hero chosen by the Goddess Herself to kill the Demon Lord.No matter what your purpose is, no matter who you are.Even if the whole world and everyone close turns against me...[The target, ‘■■, the Hero’, has been dispatched.][Contract complete.]...The Protagonist cannot be allowed to live.

He had served in the strongest Special Forces, Heavenly Sword Special Force. As the commando of commandos, he created the Netherworld in the western underground world and became the formidable Oriental Yama. He said, “I’m Liu Feng. I’m adept at two things: killing and saving. If I want to cure someone, even ghost soldiers can’t take him away; if I want to kill someone, God can’t save him.” Now he was the bodyguard of Yang Shiwen, who was the daughter of the richest family in Donghai City and suffered from a rare disease. Could Liu Feng save Yang Shiwen’s life with his amazing art of healing? What would happen to his double life?

- Description from Novelupdates

A Di [legitimate-born] daughter of a noble house turns into an abandoned daughter. No father to dote on her, no mother to love her, no problem. She uses one silver needle to save a dying man. What’s so unusual about a medical injection? She roams all over the world with a scalpel in her hand. Cutting throats, cutting open abdomens, cutting open skulls to mend bones. With amazing medical skills and ethics, she gathers a flock of officials, obtains the will of heavens, gains public favor, and receives Taizi’s [Crown Prince] doting. In the midst of a powerful momentum, her cheap father comes to reunite. She coldly refuses to go home or acknowledge ancestors.

The strongest King of Soldiers returns to the city of flowers, becoming his fiancée's cohabiting bodyguard!