*KNY X MHA* ( this is just a story for fun and it's a AU) What If nezuko and tanjiro didn't have a family because they ran away due to abuse from they're father? it was just them. and they had a unknown sister? and they were living in the mha world. And nezuko's quirk was fast fighting skills until she turned into a demon and got demon blood art and regeneration, and her true form was a scary looking demon (like kny). and tanjiro's had 2 quirks water and sun breathing. He uses it just like kny except when he uses it the quirk comes out of his hands except a katana. Eri knew she had 2 siblings due to her overhearing overhaul talking to a man to find them. She found out they ran away before her quirk killed her father. She knows how they look like because she has kept a photo that she found on the floor of overhauls lab. tanjiro and nezuko got a letter... what will happen? (present Mic and aizawa adopt eri) Aizawa x Mic