MTL - Demon Slayer: The Beginning of the Game Opens the Way of Reward for Diligence - Chapter 50

After breaking up with his girlfriend, he accidentally acquired a genius system and rose from there against the heavens, becoming invincible..

- Description from Novelupdates

“World” is a game renowned for its remarkable freedom.

In “version 3.0”, I made the decision to maximize my focus on boosting magical abilities!

All stats now revolve around magic! But In turn, I embraced a substantial number of disadvantageous traits.

However, that is inconsequential. I am determined to forge the ultimate Wizard character, It matters little whether the character’s outward appearance resembles a walking corpse.

Yet… What is this?

I have suddenly transformed into that very character – a character with prodigious talent, yet unable to survive a single day without relying on drugs.

A teenager named Evan Mason was reincarnated into the magical world of Harry Potter and goes to school at Hogwarts!
With only his knowledge of the future and great talent for magic, he takes the path towards the top of the magic world, only to realize that ever step he took, changed everything!

- Description from Novelupdates

Broken-hearted and drunk, Yoshida, a 26-years old salaryman, stumbled upon a runaway-from-home high-schooler on his way back from the bar.

“Hey, you. JK.”*

“What the heck are you doing out here. Go home already.”

“Uncle, let me stay at your place for the night.”

“You can do ‘that’ to me if you let me stay.”

“If you meant that as a joke, it’s not funny.”

“I’m not joking. It’s fine by me.”

“Then allow me to tell you that I have no interest in brats.”

“Hmm?”

“Then, just let me stay.”

Notes:

[*] JK is slang for Joushikousei (high school girl)