Occurs after a man fucks a woman in the ass and the woman notices some of her shit is on his dick so she decides to perform fellatio to clean his member hence, a downtown brown.
When engaging in anal sex thrust balls deep when your partner is unsuspecting, and at that very same moment take out there arms. When they bash the ground say "you've been downtown browned", ejaculate then get ready to run like hell!
I heard last night Mr. Folland gave joe a huge downtown brown, i havent seen joe since!
I totally gave Shawn's mom a downtown brown last night, she was super pissed.