I am, Flame-Chaser of Previous Era - Chapter 53: Herrscher of Thunder

Aomori, who has a monster-fighting system, came to the world of One-Punch Man and gained the ability to enter various instances.

Therefore, “Founder of the Hero Association”, “NO. “And other titles fell on him one after another.

Comprehensive flow, the main world One Punch Man.

Completed dungeons so far: Pokémon – Demon Slayer – Sword – Pokémon – Digimon – Spell Return – Yokai Comprehensive World (Girls that Noragami Inuyasha can see, etc.) – Pokémon – One Piece-re0-Dragon Ball wait.

- Description from novelbuddy

Alex, a veteran soldier, meets an unexpected end on the battlefield. But instead of the final rest, he finds himself reborn into a new world—the magical realm of Harry Potter. Now a young boy, Alex is born into a Muggle family. Yet, despite his non-magical origins, his disciplined training and fierce determination uncover a rare, powerful talent for magic. With a world of spells, wands, and ancient secrets ahead of him, Alex will need every bit of his skill to face the growing darkness led by Voldemort. It’s a time before Harry Potter’s birth; James and Lily Potter are still alive. Join Alex’s journey as he navigates his way through Hogwarts, learns the mysteries of magic, and rises to face the deadly challenges that await, determined to become one of the greatest wizards in history.

Volume 1 (Set between volumes 13 and 14)

A series of short stories set before the events of volume fourteen including how Team GROUP was formed.

Volume 2 (Set between volumes 16 and 17)

A series of short stories including two separate meetings between Touma’s and Mikoto’s parents, two tales involving two of the Level 5s of Academy City, and other funny stories involving some of the characters.

Despite being the ruler of a nation, nobody was willing to marry the vicious man with a bloodlust.