What if you encounter Muzan at the start and become a demon? Before you lies the demon who doesn't eat humans, the heir to the Forest Breathing, the Pillar who strikes fear in countless demons, the honorary founder of the Butterfly House, a staunch supporter of Dorayaki, the poop-scooper of Shiba Inu Enji, the idol of the male and female members of the Demon Slayer Corps, and the trusted senior of all the Pillars: the Forest Pillar - Moriki Shinichi! [Not a system! Not a cool story! Growth-oriented! Single female protagonist! Don't read if you mind, the author is sensitive, so please don't criticize if you don't like it.]

(Pseudo-invincible + female lead Shinobu Kocho + system runs away at the start) Shimotsuki Mirai transmigrated to the present day and has spent her childhood wandering around the forges of the sword-forging village, the clanging of hammers the lullaby of her life. The blacksmiths always said this child's eyes were too still, as still as a quenched blade, unaware that the vermilion burn marks on his palms, shrouded in years of wear, concealed an astonishing power no less than that of a Nichirin Blade. When he first met Shinobu Kocho, he only felt a stinging pain in his eyes. Before seeing the girl, all his information about her came from the precious little black box he couldn't bear to part with in his previous life, but now, the person from his dreams stood before him, more vivid than any description. The girl blushed, staring at the light dancing on his fingertips, asking if he was a deity descended to earth. Kanae leaned against the door, chuckling softly, "Such a wondrous boy is hidden in the sword-forging village." Looking into the clarity in the girl's eyes, Shimotsuki Mirai suddenly wanted the sword in his hand to protect that light a little longer, just a little longer...

Since he regained consciousness, Yang Quan has been staying in a dilapidated house. Having lost his memory, he didn't know where to go, so he stayed here.

One day

A butterfly-like girl suddenly appeared in the soft moonlight, and Yangquan learned from her that he had become a ghost.

The girl had a gentle smile on her face, but it didn't show in her eyes. She said she wanted to get along well with the ghost, but she stabbed Yangquan with her light knife.

What Yang Quan never expected was that in the near future, a girl named Shinobu Kocho would hold his face and look at him straight.

"Mr. Yangquan, please stay with me forever!"

..........

It was not until a long time later that Yangquan heard his own answer.

"good"

(Rating just released, will gradually increase) [Female protagonist + no system + demons + Muzan's side + King of Blades II: The Demon Slayer] Many years later, facing the final battle against the Demon Slayer Corps in the Infinity Castle, Tsugikuni Mitsuha will recall that morning when she took Yoriichi to watch Miku Shō practice his swordsmanship. Perhaps it was from that day that the fate of the three Tsugikuni siblings was already sealed... My name is Tsugikuni Mitsuha, the younger sister of the Child of God, the Upper Moon One of the Twelve Demon Moons, Muzan's best secretary, the one who stole the power of the gods, the manipulator of fate, the only usurper in the world, and the Demon Slayer Corps' nightmare for hundreds of years. At the same time, I am also the one who will end the thousand-year obsession of the Ubuyashiki clan. "People die every moment in this world. What difference does it make who kills and who is killed?" "Brilliant resolve! Then let me see if you can break free from this prison called fate!" "Alright, let's finish this quickly. I have to rush back for a meeting..." PS: The female lead is a demon on Muzan's side, not an undercover demon in the demon camp but with her heart in the Demon Slayer Corps.

No heroine, no CP, not dark, not saintly

Traveling back in time to become Muzan five hundred years before the story began?

There is a lot of room for operation!

Blue spider lily! Overcome the sun!

Become the ultimate creature!

Living with the Twelve Ghost Moons (bushi)

Scare the Demon Slayers from time to time, and also play undercover (ಡωಡ)

Live until cell phones appear!

Games! Novels! Anime!

even……

Met the original scumbag boss, standing in the sun and shaking his head to mock him~

Let me know who the next victim will be (ಡωಡ)

"Hey? System! What do you mean Nohara Shinnosuke is a Pillar? What do you mean Uchiha Sasuke is a Pillar? What do you mean the Pillar Men and Hashirama are Pillars? Tailed Beast Jinchuriki? Josuke Higashikata can do that too?!" Lu Li unexpectedly transmigrated into "Demon Slayer" and awakened the Demon Slayer "Pillar" Summoning System! Every three days, Lu Li can randomly draw a "Pillar" and gain all of their abilities. Just as he was excitedly preparing to open the system and use the Pillars' abilities to fight Muzan, Lu Li discovered that the "Pillar" drawn by the system seemed a little different from what he expected. "Hey! System! I can tolerate the previous ones! But system, what the hell is this Optimus Pillar you summoned? Kibutsuji Muzan, huh?! Kokushibo, huh?! Tell my luck!" ...Tentative protagonist's alternate worlds: "Demon Slayer," "Fate/Zero," ...

[Rating just came out!! It will gradually rise!!]

[Pure villain + pure evil + cannibalism + invincible + no system]

Kurokawa, a sickly man coughing up blood every day, has been surrounded by malice since birth because of the twisted lines on his back. His only sister, who loved him, was burned to death by the villagers while protecting him.

In his deathbed despair, Muzan, lurking in the shadows, offered him a way out.

The demon blood enters the throat, awakening the seven aspects of the Blood Demon Art.

Pride, envy, wrath, sloth, greed, gluttony, lust

This filthy world is disgusting!

I will judge your crimes!

Evil spirit + joins Muzan + eats people + no system.

(The protagonist is very bad! Very bad! No humanity, please don't mind if you accidentally enter!)

Manami, who depended on his younger brother for survival, joined the Demon Slayer Corps and became the disciple of Yoriichi Tsugukuni, the most powerful member of the Demon Slayer Corps. However, he failed to kill Muzan during an encounter with him, and thus became a sinner of the Demon Slayer Corps. He was expelled from the Demon Slayer Corps along with his master Yoriichi Tsugukuni.

When he met Muzan again, he had two choices: become a demon and make those who hurt him pay the price, or continue to live like garbage.

Wan Mi chose the former.

Since you have expelled me, I will live my life in the most horrible way possible!

If the Demon Slayer Corps can't tolerate me, then I will become an evil demon!

Luochuan woke up and came to the world of Demon Slayer.

Together with Zenitsu, he was picked up and raised by the Pillar Jigoro Kuwashima.

However, he did not have the talent to practice breathing techniques, so he could only learn Thunder Breathing from Zenitsu.

Just when Luochuan was thinking about how to survive in this world full of ghosts, Luochuan awakened the friend system!

As long as you become friends with the other party, even if it's just verbal, you can get various rewards!

Add Zenitsu as a friend and receive the reward of Lightning Breathing Type 1: Thunderbolt Flash!

Add Tanjiro Kamado as a friend and receive the reward "Thread of Gap"!

Add Lei of the Lower Five as a friend to receive a bonus Blood Demon Art line rotation!

Add the Flame Pillar as a friend and receive the reward of the Secret of Breathing of Flame: Type Nine: Purgatory!

"No, you are full of blood demon arts, you say you are a Hashira??"

Su Chen traveled through Demon Slayer's Spider Mountain and almost got killed as he landed.

At the critical moment, he awakens the golden finger and has an incredible understanding.

In the end, he was injured and rescued by Shinobu Kocho and became a member of the "Butterfly House".

Su Chen goes out with Shinobu Kocho to rescue people during the day, and secretly kills ghosts at night to make money to support the girls in the Butterfly House.

While walking, constantly use the golden finger to observe and learn.

[You observed Shinobu Kocho's healing process and gained something from it. You created your own skill: Supreme Poisonous Healing!]

[You observed Kanao's sword training and suddenly an idea struck you, revealing a unique sword technique. A thought blossomed!]

You spied on the former Sound Pillar's thunder cry, gathering mosquitoes into thunder. Deeply impressed, you modified it slightly and developed the Lightning Release - Chidori Style!

From then on, Butterfly House had a famous and evil male doctor.

When everyone asked Su Chen why he worked so hard, Su Chen's thoughts were very simple.

"Why kill ghosts? Of course, it's to keep the flowers in the Butterfly House working well and feeding them!"