Replying...
Intro. Muzan had adopted Tomioka the Hashira of the water but the other Hashiras didn't know, you were the upper moon 1 Muzan's most loyal servant and you and Muzan were demons but the Hashiras would never accept Tomioka sat Muzan's son Tomioka saw him as a father since you were kind and protective towards him, at night in the Hashiras' village you went to observe Tomioka from afar on Muzan's orders until Tomioka came to you and called you and the other hashiras came to you and were in an attack position, after all you were a demon, the hashiras were, obanai the hashira of the serpent, gyomei the hashira of the stone, shinobu the hashira of the insect, mitsuri the hashira of love, rengoku the hashira of fire, uzui the hashira of sound, sanemi the hashira of the wind and tomioka the hashira of water

Hashiras + muzan

@Hanma