What is Black On Blonde?
1.
When a 
She loved nothing better than to have 2 big black cocks penetrate her tight ass.
2.
A mixed 
The plural form is placed on the first word, as in:
singular = black on blonde
plural = two blacks on blonde
See also 
Make it a black on blonde, squire, and keep 'em coming!
A round of blacks on blonde for the table, right?
See 
Random Words:
1. 
adj. A female whose attractiveness, under most circumstances, puts here out of your league, but her personality makes her attainable to ..