Reincarnated as the Baron's son: My Infinite Card Upgrade System - Chapter 28: Knowledge of the world.

What happens when a fanfic author with a habit of lying and scheming suddenly finds himself as a self insert during Duelist Kingdom? What happens when you have Yugi, Joey, Kaiba, and the rest encounter someone who knows all about every major player in their saga... and sees no problem with abusing said knowledge? Chaos, dear reader. Sweet, sweet chaos

Traveling to the world of Hokage, Kamiyo Colt witnessed the chaos of the Nine Tails firsthand.Without any special powers initially, he planned to develop quietly and survive until the Infinite Tsukuyomi. However, when he first trained his Chakra, his system finally activated.The system's rules were simple:By healing others, he could gain random attributes and skills.“Heal Uzumaki Naruto to receive pure Ashura Chakra!”“Heal Uchiha Shisui to gain his bloodline talent!”“Heal Sasuke Uchiha to obtain pure Indra Chakra!”In this way, Colt steadily developed his abilities over more than ten years.During the Fourth Ninja World War, when the ninja coalition saw him suddenly knock out the Six Paths Madara with a single punch, he looked innocently back at them.“What? I'm a medical ninja. Doesn't it make sense to defeat him with one punch?”

An 18-year-old poor college student tried to apply for a job as a tutor but his life almost ended as demons' meal. In his last breath, a mysterious woman gave him a strange power. When he opened his eyes he had turned into a demon with a system that would turn him into… A pervert.

Now he must lived with his dual identity as a model student named Ethan and an incubus named Damian.

In a future city intertwined with science, magic, and various races, a fearsome villain lives.“How dare you try to use such a young child. Do you have no conscience?”“It’s truly regrettable. To think that this girl could be the key to eradicating a den of evil.”“You can rest easy now. We will definitely protect you.”Sorry, but I’m actually that villain…It seems like a serious misunderstanding.