Katsuo's in the first year of middle school.

Now, his cursed energy manipulation, which allows him to make short work of grade two CB's, and probably even grade one's which he never encountered, met a bottleneck. It could still improve but its progress was so slow that it was trivial, he felt that he was applying it in the wrong way and that he was missing certain important knowledge about cursed energy, so that he could apply it more efficiently and more powerfully, but he was only one person, and no matter how hard he tried to research it, the results were minimal.

When he thought about that, he remembered that organization that he theorized to exist. If they were out there somewhere, for how long have they existed? How complex is the extent of their research about CE? How powerful are they?

He didn't have an answer to those questions so he could only focus on other things while keeping an eye out for any strange news.

Pill creation, martial arts, and social life were those things.

He hunted every CB in his city; as soon as he detected one of them, he captured it and turned it into a pill, and, as usual, there had various effects. The majority of the permanent effects of grade two pills have stopped working on him, sometimes he even wondered if he was still human, after all, he didn't know any human capable of penetrating concrete with one punch at ten years old.

Seeing the effects of all those pills he took, he was looking forward to the effects of those at higher grades, but having all that physical strength and not being able to apply it to its limits bothered him a lot, therefore he sought relief in martial arts.

He chose to learn Kyokushin Karate, because of its meaning and spirit that he thought was cool and edgy.

Uncompromising in its ways, with the sole goal of defeating the opponent, its training regime, which was done with the help of CE to protect his surroundings of himself, can even help in the conditioning of a supernatural body like Katsuo's. That's Kyokushin Karate.

(AN: To have a better idea, go to manga-raw and see the chapter 62 of the manga How to Fight)

He also did a little bit of gymnastics, but it was too easy with his superhuman body and had meager returns, so he didn't bother to continue.

The biggest challenge to Katsuo was the social life aspect, but he had to do it for several reasons.

First, he needed it to show his family that he was normal and didn't have any social problems, he didn't want them to worry, after all; he also didn't want to be known as the kid who beat up bullies, because even though he was very popular because of that, it also made everyone somewhat afraid of him, so he made an effort to make some close friends, but his biggest reason was himself. He was so focused on training and hunting that he felt that he was detaching himself from society.

It wasn't totally his fault, of course, he was an adult on the inside and his personality was never the outspoken kind, but he felt it was necessary if he wanted to maintain his mental health and communication skills.

Today was a day just like any other to Katsuo, classes ended, Katsuo played a bit with his friends and then went home, it was just a 10-minute walk, or a one minute jog if he was in a hurry, but as he was passing through an alley he heard a guttural, inhumane chuckle.

'I don't sense anything around me, where is it?'

In that instant, he felt a disgusting feeling crawling up his spine and his adrenaline started spiking, making him feel like his heart was going to burst, he looked at the alley, and he noticed how dark and hazy it was, like a mirage.

It's still daytime so, obviously, this wasn't normal.

His gaze sharpened and with one step, he entered the alley.

Suddenly, the entire environment around him changed, he was no longer in an alley, or in the city for that matter, but on an underground cave with rugged knife-like formations.

'What's this, teleportation? Illusion?'

He heard a chewing sound, looked at where it was coming from, and there it was, a xenomorph (from Alien) like thing, chewing on something, in front of it there was a small pile of humans, dead humans, he focused on the creature, and understood, it was chewing a thigh.

At that moment, he felt incomprehensible anger, and ignoring the sense of danger he felt towards the creature, he made his CE flow within his body, enhancing his already supernatural body to monstrous levels, and was ready to lung at the creature, but the creature moved its arm and Katsuo's sense of danger spiked, making him try to dodge the unseen attack, only to immediately feel pain from his right shoulder to the middle of his chest, awakening him from his anger.

In his chest, there was an ugly wound that seemed like it was done by three jagged blades, but he didn't even saw what cut him.

'That xenomorph might have an ability like me, a sure hit slash attack, and if it's like that, there's only one solution. Kill it before it kills me!!'

He quickly took his emergency stash of pills from his backpack and popped one grade two healing one and a dozen of grade two temporary enhancement pills, all with different effects, knowing from experience that the same effect can't stack while keeping an eye on the creature.

It was looking at him mockingly and smugly as if wanting to play with its prey.

Feeling the surge of power inside his body, an all-around 50% enhancement, and looking at his cruel and disgusting opponent, young Katsuo's face turned ferocious.

"Hu-Human, y-you must be t-the one ki-killing t-the weak c-curses, en-ter-tain m-me!"

'It talks!! It means it's intelligent, but it doesn't matter, you will regret giving me this chance!!'

He lunged at the creature with the fastest speed he has ever moved while not damaging to the ground, proof of his superb control and application of CE, and appeared in a blur next to the curse while strongly stepping on the ground and shooting his fist with blinding speed.

The creature was startled and dodged by a hair-thin margin but was still damaged by the shockwaves imbued with CE coming from the fist, wiping its smug face and replacing it with a wrathful expression.

The xeno-like creature rapidly recovered from his wounds but this was only the start of Katsuo's barrage of attacks and while it wasn't as fast as Katsuo, it was able to slow him down with its bizarre sure hit slash, and while the damage kept accumulating in Katsuo's body, because the effects of the healing pill ended a few seconds ago, Katsuo kept going swiftly and deadly; because as preached by Kyokushin Karate, you can rest when you're dead, until then, press forward.

Soon, the creature was cornered against the wall of the underground realm, and seeing this as an opportunity, Katsuo gathered CE in his right fist and swung it to the xenomorph's face.

At that moment, the xenomorph felt death, and feeling fear and despair, launched the strongest attack it could, managing to cut deeply into Katsuo's waist and diverting his attack to hit the underground wall but at the exact moment of impact, Katsuo released the cursed energy.

[Black Flash], Katsuo doesn't know but that's the name of the technique he has just done.

From the point of impact, fractures spread over all surfaces and shattered the realm into pieces, making them reappear in the alley from before.

Katsuo and the powerful curse looked at each other.

'I only have 50% CE left, the temporary enhancements are reaching their time limit and I have a deep wound in my waist that's going to slow me down, I've never been pushed this far before, or better I have never even tried my best ever, except against this CB. But I feel good, more focused, and aware, I'm confident I can beat this thing but I most probably won't be able to go home today, sorry mother'

(AN: After performing the Black Flash, a sorcerer enters the zone)

At that moment, the xeno's face morphed from a stupefied to a fearful expression, and started to retreat.

Katsuo thinking that it wanted to attack from a distance, lunged at it with the intent to penetrate his chest, which he did with easy success against his expectations, after dodging the curse's desperate defensive attempt.

He looked at the still alive, shrieking creature, amazed at its vitality.

'Well, that was anticlimactic'

Katsuo remembered what the creature was doing when he arrived, gritted his teeth, looked hatefully at the curse, and grabbed its head with both its hands.

"The pain you will now go through is the revenge of those people you ate, [Cursed Pill Creation]"

He activated [Cursed Pill Creation] and watched as the curse shrieked while it slowly turned into pill.

"F-F-FORG-Give M-ME!!'

Katsuo coldly watched until a black pill lay quietly in his bloodied hand.

'I've been trying my best but was almost killed, this was a serious reality check to me. If it went after my family..'

Katsuo stopped thinking, took a deep breath, swallowed the last two grade two healing pills, and felt its effects on his body. Healing-type pills have the lowest creation rate, and he only had three grade two, now he has none, and it saddened him a little.

He checked the effects of the pill in his hand.

[Special Grade Pill: 20% chance of acquiring innate technique [Jagged Claws], permanent increase in total cursed energy, permanent increase in toxin and poison resistance]

"Wow, wow, that battle was amazing, you shattered its domain barrier with your fist and killed it with your innate technique, what is its name? Or better, what is your name?"