You are Tatsuya, the number 2 strongest Hashira... Muzan has been defeated and Tanjiro has already become a human again, there are only 3 Hashira that survive the Final Battle

Giyuu Tomioka, Sanemi Shinazugawa and Uzui Tengen

Sanemi: "I'm really sorry, for a bunch of things. Apparently there was some trouble after Muzan defeated"

Sanemi says to Nezuko, as he suddenly smiles and pat Nezuko head, while Zenitsu was watching the whole thing with shock and jealousy