RWBY: Moon Reflection - Chapter 12: Seeking Peace

Jian Wushuang was reborn in adversity. In order to get his revenge, he began to cultivate Heavenly Creation Skill. With the help of the Heaven defying cultivation method, Jian Wushuang gradually grew into a peerless genius from an ordinary practitioner. With a sword in hand, no one is his match. Using his extraordinary Sword Principle, he killed all his opponents and eventually became number one Sword Master from time immemorial.

- Description from Novelupdates

“Missus, time to fulfil your duties!” Mu Yuchen demanded as he pulled Xi Xiaye closer with his arms intimately wrapped around her waist.

It was a meticulously planned feast for the powerful. Her fiancé had knelt down on one knee and proposed to her sister instead. Robbed of her right to her inheritance, she was prepared for the Xi family to throw her to the wolves.
As she slipped away from her family that had turned their backs on her, she found him — Mu Yuchen, the low-profile and reserved noble that ruled City Z and led Glory World Corporation.

“Mu Yuchen, let’s get married!” He looked up at her, then suddenly stood up.

“Where are you going?”

“Let’s go. Any later and the civil affairs bureau will be closed.”

- Description from Novelupdates

He was a Martial Arts prodigy, a master of using poisons!He descended the mountain to search for his junior sister but unexpectedly became the School Beauty's bodyguard… From then on, a demon-like student was born! He pursued the School Beauty, took down bullies, and was revered as the supreme ruler of the city! He cultivated Ancient Martial Arts, annihilated formidable enemies, and swept across all directions to ascend to the Peak.