In this story, Tanjiro wasn't able to become a human after the fight against muzan and becomes the new king of demons. Now in the modern era, tanjiro is attempting to create a serum using his blood to make his demons walk under the sun. But he discovers the new hashiras of the now demon slayer are the same hashiras he met in the past. And that is when he gets worried, because he remembers their strength. But using whats left of his humanity to create a drug that will weaken him so much giving the slayers a chance to kill him. But most of his humanity is now gone. The now modern hashiras remember their past lives and nezuko, Zenitsu, and inoskue remember their past lives.

What if Yoriichi was the ancestor of Tanjirou, what would change and what would stay the same.

What would happen if the Dance and the earrings weren't the only things that were given to them by the first sun breather, what would happen if the Kamado family had yoriichi's nichirin blade. But not only that but what would happen if Tanjirou had learned the way of the blade and the dance of the sun at the age of 7.

He will do whatever it takes to accomplish two things: Protect his sister and fulfill his father's longing. After all, it's cursed blood

I was so useless, I couldn't do anything, except quake before this man, no devil, in fear. Hello, this fan fiction is going to be where Tanjiro becomes a demon, instead of Nezuko. Before reading this I am going to tell you that this fan fiction will take a totally different path than the anime/manga does. This fan fiction is all purely based on the events in the anime, till chapter twenty, and then afterwards events that are not in the anime, only in manga, will be taking place. ~ Cover Art: @ForeverFireAnime ~Disclaimer: Demon Slayer: Kimetsu No Yaiba does not belong to me, it rightfully belongs to the amazing person, Koyoharu Gotōge. She did such an amazing job, this anime/manga is a masterpiece. So give her all the amazing credit please!!

"Tanjiro.. if you want to save your big sister Nezuko, become one of us." The man in front of him mused as he lifted his chin up with the tip of his finger. The only thing he could do in that moment was nod as his body began to shake in fear at the anticipation of what this demon would do to him. "Goodbye Tanjiro." He whispered under his breath, touching the boy's forehead. After he chanted a incantation, the red-headed boy feel unconscious, resting in the demon's arms. Nobody would ever know that that same boy would never return. Neither as himself, or as a human.

"I swear... I will turn you back into a human. Just wait, Onii-chan." * * * What if Tanjiro returned home early that night, before the Kamado Family was attacked? A turn of events would lead Kamado Nezuko to survive the night while remaining a human... whilst Tanjiro would be the one turned into a man-eating demon. --When the older brother had far higher adaptability to demon blood than his younger sister. --When the younger sister was far more talented as a Demon Slayer than her older brother. This story follows a Demon Slayer named Kamado Nezuko... and her difficult journey that she walks together with her comrades. In order to defeat her family's murderer... in order to return her brother to a human. ***** This is an 'what if' role swap story of Kimetsu no Yaiba. Demon Slayer Nezuko becomes much stronger than Tanjiro with her talent. Demon Tanjiro will also be stronger as a demon than Nezuko was in the original story. The story is rather dark and lore-based, but I'll be integrating romance elements here and there as well. ...please be aware of the word count, I write a lot as I try to be accurate to original plot as possible. Please enjoy. *** Kimetsu no Yaiba belongs to Author Gotoge Koyoharu, and Publisher Shueisha. Only some OCs belong to myself.