Demon Slayer: My Sister Is an Angel, Get It?

(Demon Slayer fanfiction + Miaojiang Gu lore + twin protagonists, with a couple and a happy ending)

OOC warning!!!

When Miaojiang Gu arts meet Demon Slayer, reason and emotion collide in a struggle of choices.

A mother and her two children fled here from distant Mingzhou, hoping they could live peaceful lives at last. Then they encountered that demon

Six-year-old Xiao Shi'an watched his mother eat his older sister. When he opened his eyes again, he was four hundred years in the future, drifting through the Taisho era as a restless spirit.

After becoming a demon, his sister Nianci lost her memories and emotions. Taking the name Ayoyi, she inhabits her younger brother's hair, while their two consciousnesses remain divided in his mind.

[Protect Shi'an… Don't eat people…]

[Kill him! Kill him and we'll be free!]

When they run into Akaza, Upper Rank Three, and find themselves unable to defeat him, they watch in despair as a lethal Blood Demon Art hurtles toward them. A hand clamps down hard on Akaza's fist, and a pair of eyes burns with murderous intent.

“Are you looking to die?”

My little brother is the only one allowed to kill him. Understand?