Everyday, Boss Is Pretending To Be Weak - Chapter 10.1 - Encountering an assassination at Feng Huang (1)

“Great Mr. Chen Yu, having been successfully elected as the leader of the human race last night, do you have anything you’d like to say to the whole world?” Chen Yu got out of bed, bewildered and still undressed, “I don’t know, I just woke up...”

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

- Description from Novelupdates

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!

High school student Mikoshiba Ryouma was summoned to a different world in the middle of a war. Sensing the malice from the one who summoned him (a summoner of the O’ltormea empire), he uses his martial arts to run away, killing important people of the empire during his escape. After the escape, he rescues two twin sisters from the hands of thieves. The sisters who can use magic, swear to serve him as subordinates. Thus, Ryouma begins his journey on the path of the supreme ruler.