I Have Awakened The Deduction System - Chapter 775 - Imparting Divine Arts

This legend tells the tale of the protagonist, Kuroki summoned to protect the demon king from the hero.

Kuroki, unbeknownst to him, suddenly came to another world. He was summoned by the demon king, Modes. The territory which the demon king overrules was in the midst of being destroyed because of the hero. He had no choice but to bow before Kuroki.

“Please save us, Savior Dono!”

Kuroki nodded, deciding to save the demon king due to an unexpected turn of event.

Follow Chen Ming as he accepts disciples, establishes a sect, and fights his way in a world that deems him a cannon fodder.
He goes against any common sense using his wits and novel knowhow to finish missions and arm himself against his cruel fate.

- Description from Novelupdates

[Moody Boy x Martial Arts Girl] [HE] [Male Lead is Crazy,]

Quan Zhisui didn’t understand why Wei Shixu was always getting beaten up by people from other schools, and why she constantly had to rush in to save him from danger. Later she found out that those people were just hired thugs.

They were paid by Wei Shixu.

“We’re through!” She firmly drew the line.

Wei Shixu smiled cheekily, “Fine, then don’t come to me for tutoring anymore. Fail the exam and repeat the grade, then let your scumbag dad and stepmom control you.”

Quan Zhisui had to compromise, “Let’s cooperate until the college entrance exam is over, but don’t go looking for trouble when there’s none.”

Wei Shixu: “I won’t go looking for trouble if you date me.”

Quan Zhisui: “I don’t date in high school.”

…

After the college entrance exam ended, Quan Zhisui went far away to university. She blocked all forms of contact with everyone, thinking that would make him give up his obsession, since it was decisive enough.

But she heard that at the awards ceremony, Wei Shixu tore up his university admission letter.

A year later, a certain repeater pursued her to her university.