I think Vapor Ghoul should have a friend who's another Ghoul who sometimes makes music with them and had the arc of Wanted To Achieve Something But Was Unable To but is Okay With It Now (having it be also a disability thing would be the easiest/most straightforward route but it could be any reason tbh)
I did some drawings of this character and I've decided he's an Earth Ghoul which is traditionally drums but he also knows about electronic music production and applies it to his own music, pretty much like I was doing when I first got into Ghost and I thought of metal as my primary genre but worked in synth-based styles.