Actually, they have been around way longer than muffins. And they were a popular fan idea to have the cutie marks and nicknames, the nicknames were based on pacman ghosts. (edit): And looking at how long the tumblr blog dates back to, I think they did create them, don't know for sure.This was created back in 2012, a whole year before Reitanna even joined the mlp fanart fandom. I love Reitanna's work so I remembered when she got into making fanart, I think it was from when she wanted a challenge to be scared and a fan linked her "cupcakes" as their challenge.