The Protagonist’s Sister Is Actually The Strongest [An Action-Packed LitRPG Transmigration and Progression Fantasy]

Listen while reading: Berserk - Behelit

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Heisenberg never had the intention to become one of Beelzebub’s puppets. Since the beginning, he intended to use him to grow stronger, and once the situation arrived, he would get rid of the Demon. 

As similar as their goals were, Heisenberg was just as cunning as Beelzebub; both of these monsters could simply not coexist or work together forever. It was a fact, a fact that Beelzebub overlooked only because Heisenberg was a human.

As a Death Apostle, he had gone through hundreds of worldlines, bringing destruction and despair to mortals, especially to humans, whose worldlines were the most he had visited. Because he always saw humans as prey, he never considered that this worldline would be different.

But the existence of Chimeras, Hunters, and more was a factor he had not calculated. Heisenberg used the power he gained from the Demonic Stigma to awaken his innate strength much further.

Much like Anna, he developed a powerful Phantom Dao Root, and with it, he awakened his first trait, [Absorption]. Once he learned of its true power and potential, Heisenberg began to strengthen it by absorbing countless monsters and demons from Dungeons on the outskirts of the Stronghold City, which were usually not regulated.

Eventually, as he strengthened his powers, a slight sensation came to him. The connection created with the Demonic Stigma that Beelzebub granted him, which felt like tight and indestructible chains around his soul, loosened.

Over time, they loosened so much that he was confident enough he could break it at any moment. But would that be even enough? If he broke it, wouldn’t he lose the power provided by the Demonic Stigma?

And then a realization came to him. Why doesn’t he just reverse its power? By “Absorbing” the Demonic Stigma and then reversing its effects as if he were regurgitating its Runic Structure, he was not only able to sap away at Beelzebub’s energy.

But with all his strength, he was able to completely absorb the Death Apostle’s Manifestation, including the Demonic Soul being carried by its vessel. With the power of a Trait, and by abusing that Beelzebub’s powers were sealed because this world had only gone through the First Awakening, he accomplished something ridiculous, especially for someone who wasn’t like Anna or Jack.

The skies continued to grow black, and the demonic beasts Beelzebub summoned remained being summoned, but the origin of it all became someone different. Heisenberg’s entire body started to melt into black goo, completely losing its original form and then reconstructing itself once more to adapt to this surplus of power.

His maniac laughter could be heard across the dark skies, and the people of Stronghold could only watch in horror as an army of demonic monsters was prepared to massacre all of them. Beelzebub’s goal to slaughter millions of people to ascend into an Archdemon was still in motion.

“This sensation… It feels like I am submerging in an endless sea of darkness.”

Heisenberg’s consciousness constantly felt like it was drowning in an endless sea of darkness, boundless and unable to see the bottom. The shadows constantly engraved their demonic force into his very soul. Beelzebub’s will struggled, fighting against him for control of their combined body.

“You dare absorb my very being, you foolish human?! Traitorous rat! I should have never trusted you, bastard! I will devour your soul whole!”

Beelzebub attacked Heisenberg’s mind, attempting to devour it with all his mental abilities. His darkness seeps deeper into his psyche, seeking to absorb and assimilate it all. However, as Beelzebub did so, he saw countless bubbles full of images and memories that defined who Heisenberg was.

“Memories? I’ll crush them so he loses his sense of self.”

The Death Apostle’s insect-like claws extended to the bubbles of memories, attempting to crush them so Heisenberg would slowly lose his sense of self and become fully assimilated by Beelzebub.

As he grasped one of such bubbles, suddenly, Beelzebub felt a strong and painful zap of energy, draining away his own strength, while visions of Heisenberg’s past passed through his mind.

“W-What is this?!”

The Demon saw a young silver-haired boy covered in bruises, wearing ragged clothes, and inside a makeshift house made of cardboard, duct tape, and branches. Surrounded by trash and flies, the anemic-looking boy was silently glancing at the body of his mother.

“Mom… Wake up… I’m hungry…”

The light of his eyes was slowly fading away, as they looked tired after not having slept for so long. Dozens of flies covered his mother’s body, which was as cold as ice and looked pale, devoid of warmth and life.

“Wake up, mom.”

The incessant sound of countless flies gathered around him, and his mother’s body constantly hammered down his head. The sound was becoming unbearable. The boy clenched his fists and then opened his jaws, catching a fly and eating it.

He was like a rabid beast; Beelzebub’s psyche imagined himself as that fly, devoured without even being able to escape in time. The young Heisenberg swallowed the fly after chewing on it and then looked into the outside world, where a man wearing a white lab coat, accompanied by two men wearing black suits, appeared at his front door. 

“Who... are you?” Heisenberg asked with a weak voice. “Are you... the doctors? Will you heal Mom?”

“It looks like nobody will miss this child.” The man on the lab coat said. “Take him.”

The men wearing black suits destroyed the cardboard house and dragged Heisenberg away. He tried to resist but was unable to fight back against them. He screamed, he cried, and he asked where they were dragging him, but they didn’t answer.

“Mom…! My mother is sick! Please help her! Stop! Why are you dragging me away from Mom?!”

As he was dragged further and further away, his eyes glowed with a crimson red hue as he started biting and gnawing at the arms of his kidnappers.

“Let me go!”

However, the man quickly smacked his head, making him fall unconscious before he could make a scene. They threw the boy inside a ban with dozens of children similar to him who lived in the poorest areas of the suburbs. Some were not unconscious, talking to themselves; others were sleeping; and others seemed barely alive.

Heisenberg regained his consciousness after a couple of minutes; the ban was already moving elsewhere while he was surrounded by children. A brown-skinned child, the tallest of all of them, was staring at the floor in silence, his tall and muscular body unlike the rest.

“…”

“Hey…! You! Where are we being brought to?!”

“…”

“Can’t you talk?! HEY!”

Heisenberg kicked him and even grabbed his hair, but the man seemed devoid of emotions, remaining stoic and immobile. The boy stepped back, finding this completely nonsensical. A voice echoed behind him.

“He’s Gustavo; he doesn’t talk. He doesn’t even move unless you show him food.”

A girl with purple hair on her left side is looking at the tallest of the children in front of Heisenberg. She looked slightly healthier than the rest but was still covered in bruises, and she wore a very rugged dress. Heisenberg sat next to her.

“What’s your name?”

“I’m Evelyn…”

“Do you know him?”

“Yeah, kind of. He lived near my house. I’ve known him since he was a baby. Since the death of his father, he has never talked again. What’s your name, though?”

“Heisenberg…”

“Such a fancy name; is your dad rich or something?”

“Mom always said dad would one day come to pick me up and that our lives would improve after that... She always said that. So maybe… D-Do you know where we are being dragged?”

“I don’t know... My sister sold me off to these guys. I assumed I would become a prostitute or something. 

Evelyn clenched her fists as she looked into the floor, a few tears falling from her eyes. She looked betrayed and heartbroken, but at the same time cynical, as if accepting her fate. It felt as if she already assumed she was trash nobody cared for.

“…”

The young Heisenberg remained silent as he took a look at all the children, scanning them and noticing a girl with short red hair, a blonde boy, a lanky guy with black hair, and... a little girl, probably the youngest out of all of them.

“Sniff, sniff…”

She was constantly crying, confused about where she was. Unlike the rest of the children here, who were between fifteen and eighteen, she was still young enough to not know many things; she was confused and inexperienced in the painful life of the suburbs.

Even her clothes looked slightly normal, not rugged or nasty. It was as if they had dragged her from somewhere else, not from the place where they all came from. A nice place, with a loving family, maybe. 

“What’s your name?”

Heisenberg approached her after feeling sorry for her, his crimson eyes glancing into her own, adorable ones.

“P-Papa said I shouldn’t talk with strangers.” She continued to sob. “D-Don’t talk to me…”

“Well, we can start by not being strangers, then.” Sighed Heisenberg. “Why are you here? Were you kidnapped too?”

“Sniff… You too?” The little girl asked.

Most of the children glanced at her; some nodded, others looked elsewhere. Much like Evelyn, some were sold, but others were simply kidnapped out of their houses. They all looked miserable.

“C-Can they let us go?” The girl asked desperately.

“They’re strong and dangerous.” Evelyn said. “If you want to live, you better just do what they say... Even if it hurts, even if it’s horrible, If you want to live... You have to do what it takes.”

“N-No, I don’t want to do that! Let me go!” The little girl stood up and started smashing the glass windows with her little hands. “Mama! Papa! Where are you?!”

“Oi, stop it!” Heisenberg dragged her back, but it was too late. The same pair of men walked into the room once they heard the commotion, scanning the area coldly. They looked at the little girl, which Heisenberg quickly hid behind him.

“Why are you protecting her? You just met her.”

“I-I don’t know what you’re talking about.”

The two men were about to leave before the girl ran away from Heisenberg and hugged one of the men’s legs, screaming as loud as she could.

“Bring me back to Mama and Papa! I WANNA GO BACK HOME! I WANNA-”

“Scram, you little sh*t!”

However, she was greeted with a punch on her face, so strong that she was blown away several meters away, landing on the floor.

BAAM!

“Arrggh…!”

The little girl started crying and sniffing; her nose was broken, and she was constantly drowning in her own blood, tears endlessly streaming from her face.

“Mama… Papa… Sniff… Buaaaah!”

Heisenberg watched the scene in silence; the two men then glared back at him. They noticed something odd about the boy. His presence constantly grew larger and larger, his eyes glowing with crimson red light. For a slight moment, they felt a chill run down their spine.

He wasn’t normal. 

“Y-You bastards… She just wants to go back home. You didn’t have to fucking hit her!”

With primal rage, Heisenberg confronted them once more. Every child in the ban watched in disbelief as the weakest-looking kid attacked the two men like a rabid dog.

He bit their legs, used his nails to slash their skin, and constantly roared and barked like a beast. He climbed their bodies with the agility of a monkey, and the two men constantly attempted to catch him until they finally grabbed him and pushed him down to the ground.

“You damn fucking ant!”

One held him down while the other started punching his face constantly; the boy’s face slowly disfigured as he was punched almost to death. Blood and teeth splatter around the floor. The children only watched, and nobody did anything. But in that moment, they learned something.

He was strong.

He went against them even knowing he could not win; he risked his life because they hit a girl, and he would probably do it again. He probably knew he would get his ass beaten to death, yet he didn’t care. 

The tall Gustavo, who had been mute this entire time, slowly lifted his head, watching Heisenberg on the floor, half-dead, the men in black suits having already walked away from the scene once they felt satisfied after having taught the child a lesson.

“You’re strong.”

That was the only word he said. Evelyn’s eyes widened as he saw Gustavo even speak. She then redirected her eyes to Heisenberg. The short-haired redhead girl also did so, as did the blond boy, and the lanky guy with long black hair glanced at Heisenberg with admiration, running to his side.

“Are you okay?! "Let me tend to your wounds!” He took apart a piece of his clothes to wrap around some of Heisenberg’s wounds, stopping the bleeding. 

“You were so reckless... Why did you do that? Don’t you have common sense?” Evelyn asked him.

“This guy’s crazy... Hahah…” The blond boy laughed.

“I could have fought too if I wanted.” The short-haired redhead said.

“Big brother… Why did you do that for me?” The little girl approached him.

“I just wanted to know your name.” Heisenberg looked at her.

“…Annabelle.” She sighed. “T-That’s... my name.”

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