Delve - Chapter 5: Alone

The unparalleled Demon King Ye Xuan, who was able to heal the death or the living alike and holder of the medicine Holy Scripture, was betrayed and killed by his fellow Demon Kings. But he reincarnated into the body of Ye Xuan, the prodigal son of the Ye family and vowed to himself that he would return to his peak and take back everything that belonged to him!

- Description from Novelupdates

Shi Hao, a young man, managed to turn the tables on a powerful figure trying to possess him. He gained countless cultivation techniques, martial skills, formations, alchemy knowledge, and talisman arts, setting him on a legendary path.Now, every genius and tyrant must bow before him.Those who refuse? They'll be eliminated!

When encountering demons, a young man with two horns on his head, red hair reaching his waist, and an extremely handsome appearance leads the demons to the front.

Youdou: Actually, I really don’t want to be a master of monsters. This profession is completely useless. My ideal is to become a magic stick…, bah, it’s to become a great onmyoji.

All the monsters: My lord, wake up, you are the leader of the monsters yourself!

- Description from novelbuddy

Being given a chance and reincarnated is nice and all, yet why do I have to become that male friend who just watches the protagonist flirting with his harem?---World: Kaguya-sama: Love Is War - Hyouka ----