Reincarnated as Denji with a Trial and Error System. (On Hiatus)

P.O.V. ???

And here I am, fleeing from law enforcement with powers they've never seen before, and the little parsley-haired guy is chasing me, "oooh, so scary."

"Hey, tired of chasing me even on a Friday? Sorry for telling you just now, but being a full-time employee sucks, hahah!"

I dodged a giant fox head that tried to devour me alive. I did a double somersault twist in the sky and then smiled.

(Fluttering Butterfly!) - I attack by spinning with a kick directly to the creature's head, repeatedly, as if bouncing, until its skull cracks and it disappears.

"Seriously, I love Lego Ninjago! Hahahahaha!" - I think loud to myself. - "What's up, Jimmy Five? Is the pineapple on your head hurting? Paint it orange, then a sponge will come in! HAHAHAHAHAHAHAHA!"

"WHAT THE HELL ARE YOU TALKING ABOUT, YOU IDIOT!?"

And there he was... a complete jerk. With shark teeth on his face, which was comically contorted in rage. His pineapple-like hair would make any sponge "hard", and his suit was utterly ridiculous... Aki Hayakawa.

"And does that even matter? Damn dude, you've messed up my monthly shopping!"

"You're a terrorist, you idiot! Did you think no one would recognize you!?" - Aki makes a very pertinent point that I hadn't thought of yet... AH, SCREW IT!

"Anything that threatens the government, they consider terrorism, are you dumb? I can't even help humanity without being a threat, go figure..." - I say, shaking my head in disapproval while mid-air.

I hear a gunshot in the distance and activate my Airjitzu, a colorless bubble forms around me and I start to float, at the same time, this bubble protects me from the shot, directing it slightly off course, allowing me to dodge.

"Do you need all this just for one guy!?"

"When the idiot is you, yes!"

Well, now that you're getting used to the mess, let's have a little summary before all this happened: Denji in this timeline never met Pochita, died to a random demon before the original timeline's zombie devil incident happened, and a nerdy guy into underground stuff, me, reincarnated into his body.

So, good summary? What? You wanted more details? No way, that already drained too much of my brain energy...

P.O.V. Narrator

Going back in time a few months, on the day Denji died to the fraud demon, a person who could be considered a complete stranger possessed his body, unintentionally, after also dying in another reality.

Unlike many generic fanfic stories, here the protagonist didn't have a chance to make a wish or anything like that, he simply perished and appeared in his new body, partially buried under rubble.

"Ouch. Did anyone get the truck's license plate?" - He gets up, with a strong headache and still groggy from sleep. - "Who said that!?" - He looks around confused, not recognizing his own voice, with the surprise quickly removing the lack of consciousness he had at the moment.

Finally recognizing the surroundings, he finds himself trapped by concrete and metal debris, luckily without any part of his body injured, at least.

"Okay, how did I end up here and... In a body that's not mine?" - He wonders, looking at his hands and seeing them much more calloused than he remembered.

"The last thing I remember is... Oh, right, my house was invaded and I died, it sucks to be born privileged..." - He says with the corner of his mouth descending in disgust and arms crossed, as far as he could.

"Well, if I reincarnated, I must have some privilege. Inner power?" - He tries to feel something inside himself and nothing. - "Super strength?" - He tries to lift the piece of concrete that was pinning him to the ground. - "Haah... I just need to be a system. Status... Open status window... System?"

{Initializing S.T.E.}

"Oh, go to hell. SUPERIOR ELECTORAL COURT NOOOOO!"

{System of Trial and Error online}

"Aaaah, alright."

A few seconds pass in silence, with nothing happening.

"Okay, what does this do? Is there a tutorial?" - He waits for a window with instructions to open, but nothing happens. - "Do I have to guess? It makes sense if I have to try... Okay, show me the system rules tab."

{System Rules:

1- To acquire abilities through the system, knowledge about such ability is necessary;

2- Trial and error are necessary for understanding and gathering knowledge about the ability;

3- The user must know how it works or how to execute it;

4- Cosmic abilities are outside the system's jurisdiction, abilities that are trained a lot and consequently fit into the "cosmic" category can still be acquired.}

"So, I have to struggle to get really cool stuff... Boring. Well, I think if I received a system, there's a reason for it, what is it?"

{Main Mission:

(The Weapons of Balance)

Your primary objective is to arm humanity against demons, to give it a chance to defend itself and no longer depend on the powers that demons grant.}

"Wow, interesting. I thought it would be the cliché of 'defeat the demon king' adapted to the universe I'm in, and looking at this description... This sounds like Chainsaw Man."

Thinking for a while, he decides to try to create a mapping ability.

"I want to create a mental map based on what this body has already seen, can I do that?" - He asks the air, since the system didn't have a physical body or a screen, it was just an illusion in his head that there was something there, so he didn't even bother trying to summon it.

{Ability |Low-Precision Living GPS| created}

Without wasting words, he tried to see where this body had been, closing his eyes a map like one drawn on paper appeared, with drawings to represent things and a city next to Tokyo was his current location, he was in a neighborhood named "Fuefuki" in a city called "Yamanashi".

A dislike for Japanese names was present, since he was South American and understood nothing. Even with difficulty in locating himself, he quickly adapted to the map and explored it slowly, the map itself seemed to improve as he saw the places and reinforced the memory unintentionally.

The young man could see some "marked" points of interest, like a distant midpoint marked as home, which was one of the most detailed places on the map and which he could even see up close, realizing it was a dump and that he was very poor.

"No, my privileges! I worked so hard to have them, had to stay 9 months in gestation...!" - A self-aware daddy's boy of his situation, what a rarity!

"Well, that was useful and introduced me to some interesting concepts. First, the map is based on my memory, so if I have a Mandela effect and swear there's a street in a certain place, it will be marked as existing... Second, it was exactly as I asked and thought it would be, so the rules are very literal in what they said, that being said..."

An attempt to create an ability without having to say it out loud was made, with the special ability being super strength, but instead of just increasing strength, it's super strength that removes the natural limits of the muscles, the limit that's preventing the body from getting hurt all the time.

{Ability |Unrestricted Strength| created}

"Okay, daddy, time to get out of here!" - He says to himself and starts the test drive of his power.

Using the ability, he throws the piece of concrete above him to the side and immediately turns off the power, with groans of pain.

"DAMN! I forgot that if I remove the limit that prevents me from hurting myself, I hurt myself!" - He complains with an almost crying face, just out of spite and not genuine desire to cry.

(Okay, I need something to increase my recovery rate... Maybe if I increase cell mitosis, but then there's the problem of nutrients...)

(If I increase my heart rate, there won't be that problem anymore, the hard part will be if I increase it too much and burst my veins unintentionally) - The young man is in dilemmas of this kind for a while, until he decides to try to create an ability that forces the system to prevent self-destructive abilities.

So he did exactly that. As a new rule, now, if the system perceives that the abilities it is creating cause great harm to the body, it will prevent their creation.

Now... how to contain the pain caused by the super strength he created? The answer is clear, adrenaline!

One of the body's natural compounds responsible for inhibiting pain in extreme situations, also artificially created by human hands to prevent soldiers from dying from shock in combat and later widely used in medicine for patients with excruciating pain.

With that in mind, the "nerdy guy" created an ability that allows a little of the substance to be released into the circulatory system to prevent pain.

"And now, only one thing left to recover faster..." - Thinking for a moment, this time he had an idea for something more far-fetched... a new organ in his body.

A natural fan, but instead of generating wind, it sucks in air and converts it into physical organic matter, thus, closing his wounds and recovering his body, this organ would be located in his trachea. To his surprise, this was accepted by the system and gave him a new look at something he had been considering "useful, but not powerful" until then.

{Ability |Wind Recovery| created}

"HAHAHAHAHA! THIS IS AMAZING!" - With that said, he takes in a long breath and feels the pain gradually stopping bothering him. - "And this gets me ready for another round!"

With his strength restored, he removes the debris on top of his torso, with the adrenaline ability activated before and preventing him from feeling the severe pain again, the process was repeated several times until enough of his body was freed to be able to sit up and facilitate his exit.

With a jump propelled by his desire to get out, he stays in the air for a moment and lands gracefully... like a sack of potatoes falling to the ground.

"Ouch..." - He says, but soon regenerates by inhaling more air.

Observing the starry sky, he sighs at the sight of the large number of stars, and also... the 2.5D trees?

Looking at himself, he was amazed, finally noticing that his body was like that of an anime character.

"First thing, a mirror! If I'm in an anime, I want to know if I'm a background character, secondary, or main!" - He starts looking around, seeing some devastated streets, moving forward, he tries to find a car to look at himself in the rearview mirror.

"Enjoying" the view, he becomes a little worried about how life will go on, he's sure it's going to be radical, because if he really is in Chainsaw, there's a lot of potential to be explored in this universe, not only with existing things but also with things he knows.

Walking a little further, he comes across a fallen motorcycle, but with the rearview mirror almost intact, crouching down and looking at the reflection he sees...

"Damn, I'm the protagonist... If I'm Denji, that means..." - He looks down, with tears in his eyes, and lowers his pants.

 "I'M A MONOBALL!"