MTL - I Have a Store In the World of American Comics - ~ Three hundred and twenty-four

Leon, a man who tragically died of exhaustion due to his sister's otome game, unexpectedly finds himself reincarnated as a young aristocrat named Leon Bartfort. However, he soon realizes that he is not alone in this body. Another mysterious entity already resides there, its voice echoing in his mind.Who is this second consciousness? Is it a friend, an enemy, or something far more sinister? Will they be able to come to an agreement to share control over the body, or will a fierce struggle for dominance ensue? Or perhaps their interactions will lead to unforeseen consequences?Intrigued? Then start reading!

Everyone must have a few regrets in their lives, and for Mykel regret was publishing this novel on the internet. Because of this failed novel he wrote, made his career down the hill as an author. Thanks to this novel, he lost his passion and he lost everything that he had.

"I wish I can destroy this novel so that nobody will be able to see it or remember it anymore," Mykel said.

That was what he wished for, and for some reason, he went inside that novel of his and as himself in the story that didn't suppose to exist?

Mykel smirked and grinned as he looked at the system.

[You are the creator of this world, you will have the access to the command system. You are free to do anything as long as it is listed in the command system]
[Please enjoy and have fun]

"Heh, then I will turn this world upside down," Mykel said as he glared at the notification in front of him.

In the year 2057, the world has become a corporate-run utopia for the super-rich, and a hellhole for all the rest. Catherine 'Cat' Leblanc is an orphan that is about as far from super-rich as one can be. When the Incursion alarms start blaring and the sky starts raining hungry xenos, it's just another blemish on an already piss-poor afternoon. A cyberpunk magical-girl alien-invasion LitRPG.It’s exactly as wild as it sounds.

The simulation is over, and the entry is obtained: a showdown!

Looking at this entry, Zhao Meng was stunned.

“How should this term be used?”

“Hey! Here’s a wounded fox!”

…

A few years later, a woman who looked like a fairy appeared in front of him, and said:

“My lord, I’m here to repay my favor!”

This book is also called “Starting from Transforming Monsters”

- Description from novelbuddy