#slayer!sans

In this Au, Monsters weren't sealed in the underground. They were at peace and everything was going well... However, there was a threat.... a cannibalistic beings called Demons.

Demons are different to Monsters and Humans.

Unlike Humans, Demons can't infect nor eat Monsters as they are entirely made of magic so if Muzan were to inject his blood to a monster, the said monster will dust on contact.

Magic also can't kill Demons as they regenerate faster than a human, however a boss monster can incapacitate them until sunrise.

Demons and Monster do however live longer but a Monster can age when they had a child. Demons, however, eat human flesh to become stronger and live longer unless they're decapitated by Slayers

Demons had already killed so many victims from their hands just for immortality...

One of the victims was Gaster and Papyrus... Sans' only family.

Sans came home from getting some herbs until he saw his baby brother dead, his father was above his body as if trying to protect him..

Undyne (Papyrus's best friend) saw that Sans was there and blamed him, thinking he was the one that killed them.

Kagaya soon found him in the woods and took him in

Sans trained his body despite having fragile HP but he had to do it. He also created his own Breathing Style

Karma Breathing

1st Form, Judgement - Sans can sense how many victims a demon had killed, The Demons can feel their sins crawling on their back

2nd Form: Stab of Guilt -Sans delivers stabs on the Demons chest as a way to feel something like guilt

3rd Form: Execution -Sans beheads a demon cleanly

Final Form: Karmatic Retribution- Sans swipes his sword at his opponents, each swipe can make the demon deal a lot of damage. If it killed too many, the damage also applies.

He took the entrance exam at the age of 17 and became a Hashira at the age of 19.