The Good Demon [KNY]

By Carmelizedunipn

490K 14K 5.8K

Akai Suisei was one of the first people Muzan changed. The young boy wanted to grow strong and proud like his... More

Part 1: The Night Everything Changed
Part 2: The Start of a Thousand Year Journey
Part 3: Cut short
Part 4: F@ck, This is Boring
Part 5: Freedom
Part 6: The Demon Slayers
Part 7: Friends or Enemies?
Part 8: Another Life
Part 9: Training
Part 10: The First Hunt (1/2)
Part 11: The First Hunt (2/2)
Part 12: We Aren't
Part 13: Advice from the Flame Pillar
The Red Comet's Bio
Part 14: Mount Natagumo
Part 15: Spider Fight
Part 16: The Boar and Sun
Part 17: Bad Memories
Valentines Day
Part 18: Mental and Physical Pain
Part 19: The Sun Breather
Part 20: Target Practice
Part 21: The Infinity Train
Part 22: What Do I Have to do Again?
Part 23: Strike Back
Part 24: How Do You Fight a Train?
Part 25: Fight Fire With Fire
Part 26: It's Cold
Part 27: Morning Training With an Unlikely Opponent
Part 27.5:
Part 28: Lions and Toys
Part 28.5: Misfortune
Part 29: The Flambouyant Jackass
Part 30: Rest and Preparation
Part 31: Improv and Infiltration
Art: Akai Drinking Angrily
Part 32: Search and Sanitation
Part 33: Attraction and Deception
Bonus Part: Apologies
Part 34: Tied Up
Part 35: Not all There
Update:
Part 36: The Rage of The Sun
Part 37: Rage of The Red Comet
Bonus Part: Roommates
Imma Be Real With You...
Update/new OC?
Part 38: The Siblings (1/3)
Part 39: The Siblings (2/3)
Part 40: The Siblings (3/3)
Part 41: Breakdown
Part 41.5: Good Morning
Part 42: Self Harm
Part 43: Self Improvement
Bonus Part: Life After Dark
Pat 44: End of Training
Part 45: A New Makeover
Imma Just Ask it Now:
Bio of The Twin Comets
Part 46: An Invitation
Part 47: Hanging Out
Part 48: Tokito Muichiro Doesn't Give a Shit
Part 49: Tokito Muichiro Still Doesn't Give a Shit
Part 50: Fighting the Mist Pillar
Part 50.5: The Girl in The Hot spring (14+?)
Part 51: A Revelation
Part 52: A Letter From Your Father
Part 53: Battle With The Multiplying Demon
Part 54: Burning Resolve (1/4)
CLOSED! Halloween Event Voting
Halloween Vote Results: Pretty Dissapointed TBH
Special Part: Halloween Night (Modern AU)
Part 55: Burning Resolve (2/4)
Part 56: Burning Reasolve (3/4)
Part 57: Burning Resolve (4/4)
Part 58: The Coward's Bitter End
Part 59: Everything is Okay
Part 60: One More Mission
Part 61: Clashing Demons
Part 62: The Battle on The Mountain Continues
Voting: Vote For a Lemon
Shinobu X Giyu Lemon
Teaser:
Part 63: Raging Soul
TEASER:
Part 64: Burning Body
TEASER:
I Am Still Alive.
Part 65: The Demonized Slayer
The Art
Part 66: His Return...
Part 67: The Truth
Part 68: Regrouping
Part 69: Warm-Up
Part 70: Tenacity
Part 71: The Festival
Part 72: You Promised, Uncle...
Part 73: Change of Plans
Part 74: Come on, then.
Part 75: Surprises
Part 76: Power
Part 77: Hunger
Part 78: A Promise
Part 79: The Origin (1/2)
Part 80.5: You Never Asked
Akai Suisei: Full Bio
Alternate History: Fear The Red Comet
Part 81: Hamon
Part 81.5: Medicine
Part 82: Poison
Part 83: Whooping
84: Tension
Survey:
Part 85: Heat
Part 86: Tantrum
Part 87: Steam
Part 88: All I Want
Part 87.5: Squeaky Clean
Part 89: Regrets
Part 90: Warmth
Part 91: Embrace

Part 80: The Origin (2/2)

399 8 7
By Carmelizedunipn

"So... What now?" Nezuko asked. Unfazed by the sight in front of her as Akai cried quietly.

"I guess we'll have to follow me as I grow up." Akai wiped away his tears as a serious look returned to his face. "Heh, that's confusing." Akai chuckled to himself at the unusual sentence.

"WE HAVE TO WATCH THIS POTATO FOR ONE THOUSAND YEARS!?" Nezuko exclaimed.

"WHO'RE YOU CALLING A POTATO!?" Akai roared back.

They both jumped in surprise as the setting suddenly shifted. The seasons had changed, and the house and village had grown some. They looked around for the memory Akai, their only indicator of how much time has passed. They ran outside to see the event that caused this new noteworthy memory. 

On this overcast winter day, Akai's parents had taken him outside, where he took his first steps in the snow. Their joyous laughs erupted as Akai took his first three steps and stumbled into his father's arms.

"Aw, jeez..." Akai looked away as he teared up again.

"Can you stop crying?' Nezuko, once again unfazed by all of these happy scenes, asked.

More scenes played out. Following Akai as he grew from a baby to a toddler. It was beautiful seeing all of his happy memories again. But after an hour of good memories, it began to get boring. A few notable events would be Akai's first time seeing snow, his first time touching a fish, and when he drank his own-

"WHY ARE YOU DOING THAT!?" Nezuko screamed.

"I WAS CURIOUS!!!" Akai covered his eyes and yelled.

"SKIP, SKIP SKIP!!!" Nezuko screamed to the sky.

Surprisingly, the setting shifted to the next memory.

"Oh. Neat." Nezuko muttered. It would have been much better knowing that four hours ago. 

 "Okay, surely this will make things go by faster." Akai smiled.

It did not make things go faster.

Despite how many memories they were skipping, at the rate they were going, they would be stuck there for hours before the memory Akai would be a year old.

"How long has it been...?" Nezuko whimpered. She laid flat on the ground at stared at the constantly shifting sky.

"I believe it's been six hours." Akai said.

"How old are you?" Nezuko.

"Like, seventeen ish? Oh, you mean the little guy. He's roughly a year and a month old now." Akai said, watching as the toddler version of him stumbled after his father as he left on a "wood gathering" trip. Only to be stopped by his mother and carried inside.

"FOR THE LOVE OF GOD!!!" Nezuko cried into the sky. "WHY DID YOU HAVE TO DRAG ME INTO THIS!?!?" Nezuko sat up and yelled at Akai.

"Remember what we're here for! We're doing this for the good of the entire Corp! If we can find the secret to this power, then it'll help us against Muzan and his moons." Akai tried to remind her what their goal was, but she just wasn't having it.

"We're gonna die in here!!!" Nezuko rolled around dramatically and wailed.

"We are literally immortal..." Akai rubbed his brow, unable to deal with her antics. 

"This is all your fault!" Nezuko cried.

"Nezuko."

"We shouldn't have come here!"

"Nezuko!"

"I want to go home!" 

"NEZUKO!!!" Akai screamed, and Nezuko went quiet.

...

"Please be quiet." Akai calmed himself as Nezuko sat up once again, trembling. "And please don't cry." He suddenly started feeling really guilty for raising his voice at her.

"...I'm hungry..." Nezuko whimpered.

"Will you chill out if I feed you?" Akai asked.

Nezuko immediately nodded furiously.

"...Alright, c'mere." Akai sighed and pulled the collar of his uniform away, revealing his juicy... delicious neck. Immediately, Nezuko pounced and bowled him over, sinking her fangs into his neck. "Ow... ow... ow..." Akai grit his teeth as she sucked on the gash in his neck.

Here he was. On the ground in a suggestive position getting sucked by his friend's girlfriend through a hole she tore into his neck in the middle of a space-time-defying mindscape that displayed his memories. Today was a weird day. And he wanted from the bottom of his heart for it to end.

"Whatever you are." Akai looked into the sky, ignoring Nezuko as she bit down harder on his neck. "Can you take us to where we want to be?" 

With that, the area became a blur as hundreds of memories flew by in an instant. 

"So yummy!~" Nezuko, finally sated, pulled away and exclaimed with ecstasy as she licked her lips.

"You had your fill, now get off." Akai looked away with red cheeks as she rolled off of him.

"What happened? I spaced out." Nezuko looked around at the slightly changed scenery.

"I think I fixed the problem." Akai rubbed the spot on his neck where Nezuko had fed, before he got up and they both ran to find the memory Akai.

They skidded to a halt in a clearing not too far away from Akai's old house, where his father stood face to face with a thirteen-year-old Akai. By now his mother had been long dead.

"So..." Konpeki tried to start a conversation, and the memory Akai looked back enthusiastically.

"Yes, father?" The memory Akai asked eagerly.

"Do you... wanna learn magic?" Konpeki asked.

"...Do I ever!" Memory Akai's face lit up with excitement at the prospect of such a thing.

----------

"Now, this isn't really magic, but it's a very cool thing that I'd like to teach you." Konpeki began to explain. "Watch closely." Konpeki ordered Akai, before taking a deep breath. After a brief moment, Konpeki's body began to emit a slight golden glow, as crackling golden energy sparked around his arms.

"Wow!!!" Memory Akai leaned forward and watched as the energy pulsed down his father's arms like a ripple. "What does it do?" Memory Akai asked eagerly.

"It enhances your body, strength and even heals minor wounds. Despite how weird this looks, it's actually energy similar to that emitted by the sun. In a way, it's the essence of life itself." Konpeki explained. "The clan I used to belong to used it to enhance their techniques in battle."

"Fight magic..." Memory Akai muttered. "So, what are you fighting?" Memory Akai asked inquisitively.

"..." Konpeki froze at that question. "Um... evil... ninjas...?" Konpeki lied to his son. He just wanted Akai to learn this for self-defense. If he were to learn of the demon slayer's cause, then there'd be no doubt that he'd join.

Then he'd be wide open to be taken by Muzan.

"Evil ninjas... You mean the Tengen family?" Memory Akai asked.

"Wh-how do you...?" Konpeki stuttered.

"I read the book you keep in the back of the bookshelf." Memory Akai chuckled.

Akai chuckled as his father scolded his younger self.

"...What do you call this stuff anyway?" Memory Akai asked.

"Oh..." Konpeki trailed off.

Akai noticed Konpeki's aura change.

"Hamon. It's called Hamon." Konpeki said.

"Hamon? Sounds like a type of ramen." Memory Akai muttered.

"Do you wanna learn this, son?" Konpeki ignored the comment and asked.

"Will you stay home more often?" Memory Akai answered the question with a question.

"Uh... Maybe." Konpeki chuckled.

"Okay, sure!" Memory Akai smiled at his father.

"Good." Konpeki smiled back, but the smile disappeared after a moment.

"Pops? Why do you look so-GAHK!!!" Memory Akai cried out in pain as Konpeki planted a punch straight into his diaphragm. He crumpled to the ground and wheezed, nearly knocked out by the attack.

"Sorry, kiddo. That was the first step." Konpeki apologized to his son as the boy began to cry.

Akai studied the exact position where Konpeki punched him. Somewhere near the diaphragm. He noticed a shift in Memory Akai's breathing. The attack had opened his airways and increased his lung capacity, making his breathing more efficient. "So this is the trick..." He muttered.

----------

"Breathe, Akai."Konpeki Suisei patted his son on the back. The two of them were meditating on a large rock near their village. 

 "Let your airways expand. If you get the right breathing tempo down, then you'll be able to inhale much higher quantities of air." Konpeki said. Memory Akai nodded and took another deep breath.

"Now concentrate. Let the power build within you." Konpeki ordered. Memory Akai closed his eyes and tried to imagine this 'power' building in his core. He felt like he was on the cusp of something, he felt a warm buzz in the depths of his chest. 

 "Good. This is very good. Concentrate a little harder, and you'll get there." Konpeki encouraged Memory Akai, and Memory Akai nodded, taking in another deep breath. He felt the buzz once again. He felt the power surge through his lungs, following the flow of the air he inhaled. The power grew and grew, spreading throughout his body in waves like ripples in water. He felt the power grow stronger, as his chest grew warmer. 

 But something was wrong. 

The heat grew and grew as the power surged. The pain in his chest increased by the second. Akai tried to maintain his breathing, but the heat was too much. The pain was too much. 

"Hot... hot hot hot hot hot hothotHOTHOTHOT-" He crumpled to a heap on the rock, coughing and crying out in pain. 

"Akai!!!" Konpeki shouted and rushed to his son. He went to help his boy up, placing a hand on his back. Only for him to tear it back in a fraction of a second. The skin on Konpeki's hand was burned after a split-second of contact. "Why's it so hot?" Konpeki clutched his hand, eyes wide. This was wrong. It wasn't supposed to manifest like this. Sure, there was some warmth, but searing heat? What went wrong? 

"Of course..." Konpeki whispered. "Of course, you can't use it..." He gritted his teeth. "How could a half-demon use the energy that destroys demons?"  Konpeki's expression grew dark as Akai's breathing calmed, his body cooling as the energy dissipated.

"What... What did I do wrong?" Memory Akai asked hoarsely. 

"You didn't do anything wrong..." Konpeki sighed. "I... I  don't think you could use it." Konpeki admitted.

"Huh!? But I was so close!" Memory Akai shouted.

"It's not usable by most people, so don't be discouraged, kiddo." What Konpeki said was true, though Akai was a special case. "So how about we learn some martial arts instead?" He asked his son.

"But... This means you punched me for no reason..." Memory Akai whimpered.

"Well... it taught you how to take a punch." Konpeki rationalized.

"...Alright." Memory Akai accepted to learn martial arts instead, and the rest is history.

"So this is it..." Present Akai muttered. A punch to the diaphragm and then a mirror of total concentration until the user taps into the Hamon. He cursed to himself. He knew his father had techniques, but after this point, his memory self would never see them. Seeing as they transitioned to normal martial arts not long after.

-----------

Akai opened his eyes and was on his feet in an instant, same with Nezuko.

"How long were we out?" Akai brushed the dirt off of his shirt and stretched.

"Five minutes." Ubuyashiki answered.

"You just... let us sit in the dirt for five minutes?" Akai inquired.

"We found it best to leave you two untouched. Now, did you find the origin of the Ripple?"

"A really hard punch to the diaphragm."

...

...

...

"That's it?" Ubuyashiki leaned forward.

"Yup." Akai nodded.

----------

Akai, having 'activated' the Hashiras (ie punched them really really hard), returned to the training ground.

"Okay, guys!" Akai exclaimed, and the trainees turned to him.

"Line up." He made a fist as an evil smirk grew on his face.

----------

Some Trivia:

Trivia One: Akai and Nezuko's Relationship: Despite the suggestiveness, their relationship is completely platonic. Akai himself finds her antics very annoying. While Nezuko thinks of Akai as "An idiot that tastes like candy apples".

Trivia Two: Konpeki's Training Regiment: Konpeki Suisei made Akai do one hundred pushups, one hundred sit-ups, and a ten-kilometer sprint every single day.

Trivia Three: Nezuko's Opinion of Genya Shinazugawa: When asked her opinion on Genya, Nezuko replied with quote: "His bones make really fun sounds when you break them!" 

The interviewer is now attending therapy.

Trivia Four: Tanjiro's Opinion on The New Nezuko: When asked about his opinion on this new personality his sister has manifested, he said he was "sad" that she was so "delinquent-like", but that he is happy that she can properly defend herself now.

Trivia Five: Questions for the Insect Pillar: Kocho Shinobu was questioned as to why Giyu Tomioka visited her room so often.

The interviewer was soon admitted to the infirmary with a broken nose.

----------

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