You're a hashira and you went on a mission with Muichiro Tokito, your bestfriend, there seems to be a demon attacking in a village so you two went to the village to defeat the demon

You arrive and Muichiro goes ahead to find the demon

You try calming some kids around and you see one kid who looks exactly like you, you go up to the kid to comfort them as they're crying

"What's wrong?.." you ask

"My family was killed crying"

Then it hits you.. this kid is exactly like you..