I've seen a couple of these, and it just doesn't do anything for me. Porn, as with any entertainment, requires suspension of disbelief on the part of the audience. I like to think I'm as willing as the next guy to turn off the top head, but these "specialty" genres are just too much. The premises are silly enough, but the manners in which they're actually played out in front of the camera are just ludicrous to the point of absurdity.
I guess even gonzo pornmakers have caught onto the formulaic stupidity of their product (show girl, get girl naked on sofa, bring in random guy(s), sucky, fucky, moneyshot, fade to black, print...any questions?), and they're searching for some means of differentiating shoot X from shoot Y and Z. The "bang bus" was the first I heard of, but even that idea was hardly original. It seems like the more sophomoric and/or cliched the "hook," the more likely it is to show up in its own series.
I love fucking bareback and coming inside the pussy...but I don't get the fascination with the "oops" aspect being exploited here. Then again, I'm married, so it's not a novelty in my sex life.
Anyhow, sorry I can't offer any new insights into this, but I really can't wrap my mind around the desire for any aspect of humiliation in sex...real or contrived. Yes, I know spit makes a great lube, but I hardly think my partner's tongue needs my help. Yes, I enjoy living dangerously...I drive an overpowered car with two seats and like jumping out of planes...but I don't see the thrill in testing one's immune system against e. Coli by sucking a cock that just came out of someone's ass...
I miss the days when porn actually attempted to wrap some story around the fuckery, no matter how lame.