Becoming evil makes you ten times stronger, but becoming a demon gives you hundredfold strength - Chapter 342 - 300: Win-Win Cooperation, The Father of the Mischievous Daughter

Apollo Kaiser, a boy who bore the unlucky fate of being unable to grow strong, was condemned by his family.

Discarded by his mother and abused by others, Apollo gives in to his rage.

However, this action results in his death. Many would believe it to be the end, but Apollo's death was a required catalyst.

The Demon Monarch System finds its heir and attaches to his soul, bringing him to a new world where he starts his journey to supremacy.

This difficult journey rife with conflict, conquest, and brutality shall serve as Apollo's temperance.

Watch as the heir of the Demon Monarch rises above all, conquers Sin, subjugates unthinkable enemies, and even brings about the destruction of worlds!

The rise of the next Demon Monarch begins...

Igor had asked him to die for the world. She would ask him to die for her. Problem was, he didn't really like dying, not for a second time, at least.

“Teacher, you know me. I’m usually a good student, with nearly 100% attendance, and I’m also eager to help the people.

Yesterday I flew to the coast to fight monsters, so…”

“Teacher, you know me. Which teacher is not full of praise for me, but things are prioritized. Yesterday happened to be the Ghost Festival. Hundreds of ghosts walk at night, so I…”

“Teacher, you know me well. I am an activist in our dormitory. Every day I call them to go to class, but under special circumstances, so…”

“Teacher, I’m a foreigner, I don’t understand what Xie said, and I didn’t know there was a class yesterday, so…”

The teacher took off his glasses and rubbed his temples, “I can tell that everyone in your dormitory has stunts, but this is by no means a reason to skip class! This class! This year! You guys are all done!”

————————

Another version of the introduction: Ultraman Delta was living in another world for unknown reasons. Originally, he wanted to be an ordinary college student, waiting for one day to find a way to return home.

But the sudden appearance of a monster disrupted his plans, and he also discovered that his roommates were not ordinary people either.

- Description from novelbuddy

The NPC sets out on a journey to defeat the Demon Lord, joined by beautiful girls he meets along the way.---This is an NSFW story, so if you're under 18, turn back now, son. No NTR, and no full-on Yuri. There might be slight Yuri—like girls kissing and stuff during threesomes—but it's not that kind of Yuri where the girls fall in love with each other while in a relationship with the MC.---