(Nezuko and Tanjiro swap - Hashira and Uppermoons swap, and others swap as well) Nezuko comes back home and finds her family dead and she sees her older brother still alive but bloodied so she tries to take him to a medic for help but a Slayer knocks them out and Tanjiro gets muzzled and they both wake up In a cave without any trace of knowing who that slayer was, Nezuko leaves Tanjiro In the cave to find something to carry him In when she has to go out In the sun with him