OMG YES THEY WOULD I LOVE THINKING ABT THIS WHENEVER I LISTEN TO MUSIC
Ceri 100% loves karaoke even though she is not the best at it LMAO, she just loves singing for the hell of it. Morty's a little more shy about it but he'd actually have a decent singing voice.
Their first time going together(one of those private booths/rooms not like a public bar) and Morty's thinking she's going to play some cute pop songs and dance around but Ceri just starts screaming death metal 😭😭 (she was retsuko before retsuko existed ok i did it first 💅) Morty's like jfc what the fuck??
Morty would sing softer popular songs cause he doesn't know a lot of them. After a while he learns more songs with Ceri and they scream sing duets together 😂😂
Cerise listens to everything though and would play more pop/fun songs for him too 🥺