Im interested in how Muzan became what he is now. and where is Nezuko ;;
I think it's symbolism the author referring that Muzan in the end was like a scared infant not wanting to die. He has always been afraid of the sun and he was so desperate to find a way to be immune to it. If that's not it then maybe Muzan was never human to begin with that he was a pure blood demon. If this is true then there could be a possibility that there are more pure blood demons like him. Hence a time skip and another ark showing that Muzan isn't really the final villain of the series.
As for Nezuko she'll probably show up soon. Though I was expecting she will help Tanjiro finish Muzan off but it's too late he's basically disintegrating like all demons.
Edited by Gravenimage, 25 March 2020 - 08:32 PM.