Looks like Edd and Papyrus have a common interest : Red Dwarf quotes ! This artwork was even supposed to be called like that by the way, but I thought it would be kind of misleading, so I changed it to a more simple and obvious one. So anyway,"ALPHABETTI SPAGHETTI" comes out from an animation called "I have played Undertale for 2 hours" (https://youtu.be/wRSsz1JWiaE), and in fact fits pretty swell to Pap' if I can say so, and "SMEG HEAD" is what's actually written on Edd's shirt, and when I found out that both these quotes are coming out of the show Red Dwarf, I decided to make this.
And yes, the background is Sans and Papyrus' house recoloured to match the colour scheme of Edd's house so it looks even more like a true crossover ! And because I still don't like to draw backgrounds :/
I also gave them baseball shirts, because I thought it would make the drawing a little less empty, and... why not ?