Yellabone, is a slang term for a Black Female with a very light skin complexion. Sometimes they are mixed, but that is not always the case, as Black people come in many different shades.
This term is used by African Americans usually from urban areas, and can be taken as offensive if used by another race.
DJ: "Damn son, did you get that Yellabone number we met at the party?"
Darrel: "Nah... she was trippin..so I said fuck her"
Elmo's weirdcousin, originating from the Drawception game "Espurr is Bored." He's often portrayed as psychotic, and even has his own variation of "Tickle me Elmo" called "Pickle me Yellmo." Ironically enough, Yellmo is allergic to pickles.
After the Drawception game "Espurr is Bored" created Yellmo, things kinda spiraled out of control from there.