This happens after Class 1A start working as Heroes. But someone or something started prowling the streets at night... (I have only seen mha until season 3 so don't blame me if it's inaccurate ;-;) (Villain Tanjiro AU don't judge hehe)

Tanjiro(demon) was transported to the Jujutsu Kaisen Universe by a special grade curse called the Vynx. That's it. :/ (Recontinued. Posting soon. Hopefully.)

For Sanemi, the final battle against Muzan Kibutsuji did not go as intended, not by a wide margin. Why he ended up in this strange place was anyone's guess, but he knew he couldn't stand it one way or the other. But, given the right nudge, maybe he could find a reason to keep fighting all the same. One-shot.

"What have I done, brother..?" were the last words the man, as he stared at his bloody hands. He had killed his brother out of hatred, even when he showed mercy and love. Centuries passed, before his inevitable death... Or did he die? He once more opens his 6 eyes, finding himself in an unknown, yet vibrant city... Night City's future is about to become more violent than ever...

{Naruto / Nezuko} Naruto y Tanjiro luchan por mantener tanto a Nezuko y a un libro que contiene los orígenes de los demonios en sus páginas sangrientas, lejos de una alianza entre Muzan y Orochimaru; mientras tanto Naruto lentamente se enamora de esta chica peculiar que puede ser incluso más demoníaca que él. ((01: Tanjiro y Nezuko: ¿Amigos o Enemigos?))

The Barrier has finally been destroyed, though what it cost were the lives of all the monsters at the hands of one. What would happen if a bloodthirsty monster like that was released into the world still recovering from the calamity that was Muzan Kibutsuji?

En una búsqueda desesperada por un demonio capaz de dominar el sol, Muzan termino abriendo un portal a otra dimensión. Ahora Sakura incapaz de usar a chakra deberá proteger a Naruto de demonios y cazadores, en un lugar donde todo es desconocido ¿O no? ¿has oído hablar del hilo rojo?

Ben Tennyson was suppossed to be home...not in Taisho-era Japan. A family known as the Kamados decided to take him in until he can get home but...it doesn't last. Ben and Tanjiro are both hurled into a world of demons, death and violence in an attempt to get Ben back home and defeat the one known as Kibutsuji Muzan. Will they reach the goal or die trying...?

Daki regretted being a burden. She regretted being too weak to take care of herself. But most of all, she regretted holding her brother back until they'd finally been defeated. She had a new life now, a second chance she wouldn't waste. Never again would she be a burden, never again would she be weak. She'll repay all the love she's been given if it's the last thing she does.

[Yoriichi, I want to be you.] This is what he always wanted isn’t it, and now at the shoes of his twins reflection, Mitchikatsu wondered if Yoriichi is a Saint. So, this is karma, huh? Or, Upper Moon One [Tsugikuni Michikatsu/Kokushibu] reincarnates as Princess Huang Beiyue. [Feng Ni Tian Xia] [Kimetsu no Yaiba]

{Naruto / Nezuko} Naruto & Tanjiro struggle to keep both Nezuko & a Book, which holds the origins of all demonkind within its bloody pages, away from an unholy alliance between Muzan & Orochimaru; all the while Naruto slowly falls for this peculiar girl who may be even more demonic than he is! [ft. Tanji/Kanao; Sasu/Saku; Zeni/Ino; Ino/Aoi] ((13: Those Who Remain))

So... what can math do? Will I ever need this out in the real world? What can math do for me? Well this is a story about answering such questions! Or my story on how I rose to power by working through horrible pain to become a winner. (Start world KonoSuba, current Kimetsu No Yaiba)(Part of the Dark Guard reality)

The title basically summoned it up. This is a story of Fairy Tail Guild watching Kimetsu no Yaiba (Demon Slayer)! Come with them as they followed the Kamado siblings, Tanjiro and Nezuko, and the demon slayers of the KnY world. No pairing for now, just pure reactions

There's another kid who sailed on the Oro Jackson aside for Shanks and Buggy. Fem!Zenitsu in OP an AU for my existing story

Tanjiro Kamado and his adoptive little sister, Nezuko, who was actually the Fire Devil, lived a poor but happy life. That was until Tanjiro is killed and Nezuko gives up her life to save his. Devastated, Tanjiro is found by the Public Safety Devil Slayers and invited to join their ranks. Now, Tanjiro must hunt down enemy devils in order to gain the normal life he wanted for so long

What if Frisk was in kny? Will they teach humans and demons to live in peace? Or will she slay them all?

Another world, where there are only four mainlands, unique yet weird monsters roaming around instead of demons, and even goddesses of odd names to boot. As fascinating as all this however, Tanjirou and his friends' only priority is to return to their homeworld, one that they've yet to find out how. Perhaps they would find the key by joining these girls in their journey.

Shirou Emiya, the person who arguably got isekaied the most in Type Moon's history. Isekai sounds fun right? Meet new people and get awesome power. An never ending adventure for our Hero of Justice. But what if, instead of just Shirou Emiya, everyone got isekaied. How will the world react if instead of getting hit by a wrench, the world got hit by an entire toolbox.

When faced with a near-impossible threat, It falls upon the most unlikely of heroes to rise up and face it. Bound with nothing but the knowledge of the future, Josuke is thrown into a time that not many can recall; forced to face an age-old enemy in the hopes to save the future from its hidden past.(Check back every week for new chapters!)

I put Jojo and Demon Slayer characters against eachother.

El heredero legítimo del Clan Uchiha, deserta de su aldea con las manos manchadas de sangre. Yéndose a otra dimensión, iniciando una nueva travesía, en un lugar donde la noche es reinada por criaturas devora hombres, conocidas como Oni (Demonios).

Remnant is a cruel world. The creatures of Grimm terrorize its citizens, the demons come along to make things worse. But the Huntsmen of the four main kingdoms and the Demon Slayers of the fifth kingdom, Japan, work together to vanquish their enemies. Centuries later, a Huntress in training and a new Demon Slayer, along with their comrades, must bring peace to Remnant once again.

Rengoku Kyojuro piensa que Hyuga Hinata es la chica más hermosa que podria llegar a conocer. AU

After centuries of defeating Muzan and traveling the world as a Demon, Tanjiro Kamado decides to live a steady life in New York, living his days in peace. The last thing he wasn't expecting was to see some espionage named Shield asking him if he wanted to join a certain initiative.

After choosing to stay in the Feudal Era, the Bone-Eater's Well had ceased to function. Or at least, so Kagome thought. A month after the battle with Naraku, the group encounters a bizarre man. Following this confrontation, the Bone-Eater's Well sends them to a different time period. What adventures now await Kagome in this new era?