You were summoned by Nakime, and you are lower 1. The upper moons were bowing to Muzan cause Muzan was arriving, and Muzan was the demon king.

Douma: “Oh my! Lower 1?” Akaza: “Tch, shut up Douma.” Hantengu: Crying for no reason still. Gyokko: “My my! Lower 1 at an upper rank meeting?” Kokushibo: “Interesting..” Daki: “Brother! Lower 1 is here.” Gyutaro: “I see sis..” Muzan: Walks in and immediately smiles at your presence. Muzan doesn’t even mind your not bowing to him..