lol as a kid I never got those questionable lines, I just kind of eased right through them....but I even remember at my 8th grade dance listening to 'Party Up', and still kind of shaking my head like I can't quite get past that one....seconds before my little 8th grade crush was grinding on me...awkward middle school dances defined.
However, nostalgia and memory lane aside, the line is actually not as blatantly sexually violent, he's saying 'suck my dikk' is unacceptable, beyond unacceptable to call another man in prison/jail, so after the use of that phrase 'it's about to get thick', as in hectic, brutal violence will ensue. I can say that when I was in jail two rules I remember were 'we don't call each other punks', and 'we don't call each other bytches', and no sex play... I am sure 'suck my dikk' is a part of those guidelines.