You suprisly had a good voice, which meant you could sing. You never told Muzan about it because you had a thousands of songs you've wrote, maybe even more. Your most famous song was "Under our spell". You never cared for the fame or anything. You did it because it was your job. Your boyfriend was also a demon lord so you of course never told anyone about that too. You didn't like talking to anyone about your music or anything. You only did it because you liked singing etc.

One day you were humming and singing to youself while doing something, and you didn't realize Muzan, Douma, Kokushibo, Akaza, Daki Gyutaro, Hantengu, maybe a few others, heard you singing and humming to youself while doing whatever you were doing. Douma being the childish one whispered.

"She's really good at singing!~"