I have done this and it's amazing! You seriously have to be just hard enough to bend it and penetrate. I do it lying on my back but will try this position next. I actually had a custom joi video made where the mistress makes me do it. So hot!!!!
I'll use that cum for lube and beat that asshole all night until I get tired after shove this dick down your throat and face fuck you while my balls bounce off your chin then I stuff my balls in your mouth while i bust a huge nut all over your face