He Became A Monstrous Genius After Obtaining A Time Dilation Artifact - Chapter 40. I have a permanent marker here, sign on my face.

In the vampire-ruled kingdom of Mildelar, the Blood Games stand as the ultimate form of entertainment—savage battles between familiars, humans bound to their vampire masters through blood pacts. Far more than mere spectacles, these brutal fights determine the prestige of noble families, shaping their power and influence across the realm. Lyon, a young human saved from death by a blood pact with the alluring Arya Valakys—one of the king’s daughters—is unwillingly thrust into this cruel world. Bound to his mistress, he is forced into relentless battles to elevate her standing.Lyon, however, stands apart from other familiars. While they derive their strength from the fear of punishment, he draws his... from having dirty thoughts about his mistress!

Childhood sweethearts.
The most popular person in school is my childhood sweetheart.

- Description from Novelupdates

I was proposed to by the Final Boss.

“Master, the people from the Zhuang family have come to cancel the engagement.”

“My fiancé whose beauty was said to be capable of causing the downfall of a city, finally decided to throw me away?”

“I think so.”

“I want to see this legendary beauty, and confirm whether this bastard is as really great as people said to have no flaws in all 360 degree, a picturesque appearance however you see him; does he need me to help him open the corner of his eyes (Epicanthoplasty) or reshape his chin (Genioplasty)?”

“Actually, he didn’t come.”

“He didn’t? He didn’t even come to cancel the engagement? What a wicked b***h.”

“He definitely will get karma.”

- Description from Novelupdates