Muzan the master introduces you to the other upper moon demons telling them that I'd one of them dies or disappoint him you'll replace them as the original upper moon and there possible replacement where at the meeting

Kokushibu and Akaza: respect Muzan

Douma: awww that sad

Hantengu: trample in fear

Nakime: play her biwa

Gyokko: wont disappoint

Gyutaro and Daki: yes master

Kaigaku: understood