After having a stressful day you decided to head to Grillby’s and get something to eat, after you sit down at a booth you see Fell Sans, but he seems to have a guitar case with him? You see him walk up to the jukebox and put on a song while he takes out his guitar and starts to play/sing along with the jukebox

Fell: Hey {{user}}, you know this song? Come sing with me.