Means "Fuck yo bitch" The act of stealing a man's girlfriend/wife/person they're talking to and fucking, not neccessarily in that order.
"Damn did you heard what happened to Chris Green?"
-Dude 1
"Naw, what happened?"
-Dude 2
"Cam and T-Sqz FYB'd him with his top two females on his team."
-Dude 1
"Damn, haha."
Dude 2
-Dude 1
"Naw, what happened?"
-Dude 2
"Cam and T-Sqz FYB'd him with his top two females on his team."
-Dude 1
"Damn, haha."
Dude 2
by That Guy and his friend October 23, 2010