That is to say, I doubt you're alone in your thinking. First off, the actual number of people that really have a 12" cock are about one in a million. Second off, the chances of getting a 12" cock into a virginal pussy are also about one in a million. As fiction, though, it can make for a good read to imagine the female squirming and screaming in pain. Triggers some of the pleasure centers of my brain thinking of it.

As for a submissive/slave toy being passed off to other, people do it all the time in real life. I am including it in the story I am writing right now. (Yes, there are more chapters coming in "Rose takes a Day Off." I've just been lazy.) It can be great humiliation and punishment for the slave to have to serve someone whom she doesn't know or that you tell her she has to serve and has no choice.