Work Text:
Midoriya panted from exhaustion. If he was found out, he would be expelled from UA. He would never become a hero. He would never succeed All Might. He would never defeat the League of Villains.
Japan, no, the world was counting on him once more.
He did not know exactly why he was doing this. He only had bits of memories that popped up occasionally. There was nothing concrete. Yet it seemed so real.
At first, Midoriya thought he had suffered a concussion from the attack in Kamino Ward. The beam All for One hit him with had nearly knocked him out. He had a migraine for days after the incident.
Then, the visions started to appear.
A black sword. A young girl with black hair and feral pink eyes that sparkled. A boy with lightning yellow hair and a tendency to burst into tears when overwhelmed. A boy (beast?) who wore a pig’s head and challenged everyone to a fight to prove his worth.
And a girl (a cute one Midoriya noted) with dark lilac eyes that shimmered and a coin in her palm. The mere thought of her made him blush. And he could not for the life of him figure out why.
Then came the names. Kamado Nezuko. Agatsuma Zenitsu. Hashibira Inosuke. Tsuyuri Kanao.
And Kamado Tanjiro.
The name sounded strangely familiar, as if it belonged to a friend he had known long ago. But Midoriya knew that he had never met someone with that name. The entire situation was driving him crazy. Familiar names that he had never heard before. A call to action so close yet so unusual. There had to be a reasonable explanation, right? Surely this had to be a side effect from the fight at Kamino Ward? He should definitely tell an adult, preferably Recovery Girl or All Might. But for some reason, Midoriya could never bring himself to tell anyone about his visions.
As the days went by, this entire ordeal became somewhat clearer. Zenitsu and Inosuke were his comrades-in-arms. Nezuko was his darling little sister. Kanao was his l-lover (Midoriya blushed as he remembered all the times he had spent with her). But they were all from another life. A life of hardships. A life of war. A life of bloodthirsty demons. It was highly unlikely that he would find them again in this life.
But something began to trouble him. All Might had told him that All for One had been alive for at least two centuries. And no matter what anyone did, he could never be killed. Many people had tried and all had failed. He had stolen far too many regeneration quirks for him to be killed by anything. The best the heroes could do was to capture and imprison him in Tartarus.
This story felt far too familiar to Midoriya. A centuries-old overpowered foe who could not be killed? One who got back up again, practically unharmed, after every battle?
It reminded him of Kibutsuji Muzan, the Demon King.
But it was impossible! All the demons were eradicated after Muzan’s death, the slayers made sure of that! The Demon Slayer Corps were disbanded as there was no use for them anymore. Humans could finally live in peace and harmony. There was no need for further bloodshed. No one had to live in fear of being eaten, killed, or tortured alive. No one had to fear the Blood Demon Arts. No one had to learn and pass on the Breathing Styles.
But now he lived in the distant future where humans had evolved and had powers of their own now. Anything is possible if a person is greedy enough to fight for it. The villains of this age were proof of that. Perhaps in the quest to make himself a god, All for One accidentally turned himself into a demon.
It looked like the Demon Slayer Corps were needed again.
Tanjiro Midoriya would have to fight alone this time.
It would take too much time to try to track down the reincarnations of his friends, if they even reincarnated. Nezuko, Zenitsu, Inosuke, Kanao…they could all be living out their new peaceful lives anywhere on the planet. No, Midoriya had his memories, so he would fight. The others did not need to remember all the pain and suffering they went through back then. They didn't need to be troubled with this. It would be better for them to live out their days in peace.
But he would need a Nichirin sword. He could not defeat a demon as powerful as Muzan without one. The chances of finding a smith in this modern world were too slim. Midoriya needed a sword and he needed one fast.
Luckily he was reincarnated in modern-day Japan. He wasn't far from the place where he wished to be buried.
This was what brought Midoriya to his current situation. His hair was covered by a dark plastic hairnet so no loose hairs would fall out. He wore plastic gloves and women’s rain boots that were two sizes too large. He wore a black face mask to cover up his freckles. He even stuffed an old t-shirt into his jacket so it would look like he had boobs. No one would recognize him now.
Midoriya took his shovel and started to dig. He didn’t know whether he had to pray to someone before committing this unlawful act, so he prayed to Kanao-chan, who was buried next to his past self. Surely, she would understand, wherever she was.
The mountainous ground was tough to break through, so he had to use a little bit of One for All to get the job started. No one was watching him and there were no cameras. He was free to use his quirk as much as he wanted.
Midoriya kept digging until he hit something hard. He tapped the shovel on the surface and there was a loud thump. He had hit wood. He had hit his own coffin.
It was then when Midoriya realized exactly what he got himself into, but it was too late now. He removed the last heaps of dirt and rock and…
…he opened the lid.
The cremated remains of his old body glimmered in the moonlight. Had he not known better, Midoriya would have thought that the coffin was filled with sand and driftwood. His heart raced. He wanted to scream but his neck ached. Midoriya felt bile rise in his throat. He wanted to vomit. Seeing a human’s dead remains was hard enough. No one should have to look at their own dead body.
He closed his eyes and reached into the ashes with his gloved hands. They were cold to the touch. They were lifeless.
Midoriya moved his hand back and forth, searching for his old sword. At last, he felt the cold and smooth edges of his sword. He grasped the handle and pulled it out.
It looked just like he remembered it. It was the confirmation he needed that he was not crazy. He was not imagining things. Demons were, are , real. He was a demon slayer in a life long ago. And Tanjiro Midoriya will be a demon slayer once more.
Holding the sword brought back many more memories. Fighting alongside Rengoku on the train and being given his tsuba. Meeting Giyu for the first time. Shinobu’s death. Genya’s Death. The final battle against Muzan. The memories flooded his vision and brutally hit his senses. He could feel the places on his body where his scars used to be. He could smell the faint scent of wisteria. His heart pounded. His brain drowned in sensory overload.
When Midoriya came to, he was lying on the ground and the sun was beginning to rise. He had to get back to the dorms before Mr. Aizawa realizes he left. He had to leave this place before someone realizes what he did.
Midoriya quickly covered the grave with the dirt and started to run off. Then he realized he had forgotten his sword and he turned back just as quick.
Someone was approaching the grave from a distance. He was tall. He was muscular. And he was angry.
“Hey you! Just what the hell do you think you are doing?” The mystery man hollered.
Midoriya bolted, not wanting to stay in that place any longer. Although he was using a little bit of One for All, the man was still catching up. Perhaps he had a speed quirk?
Midoriya had no other choice. He changed the grip on his sword like he had done a million times before and looked up at the rising sun.
And for the first time in this life.
He breathed .