Dance x Lust
Bad sans poly (Sub Night for extra points)
Dream x Dust
Cross x Killer
Ganz x Color
Kink (Killer x Ink)
Outer x Error
Dream x Horror
Ink x Blue
Error x Sci
Insomnia (Error x Dream)
Dream x Reaper
Blue x Horror
Killer x Horror
Sans x Sans
Limbo (Geno x Nightmare)
Purgatory (Geno x Dream)
Ganz x Abyss
Mecha x Kin
Mecha x Dream
Abyss x Dream (HAHA DRESS)
Killer x Abyss
Geno x Abyss
Cross x Geno
Nightmare x Horror
Another one bites the dust(Reaper x Lust x Dust)
Reaper x Cross
Geno x Outer
Outer x Blue
Outer x Fresh
Ink x Geno
Abyss x Nightmare

I can add more later.