Boulder Fisting
The sexual act of moulding a 20-meterboulder into your hand and chiselling it into a fist with your dick/strap-on. Then during sex, ask your partner to turn around and bend over, only to surprise them with a rusty hard rock up their sweet ass and ravage their insides with vigor and tenacity, flamboyantly shaking your fist around their insides before suddenly pulling out to let the juices flow inside-out and offer it to Lord Ochinchin.
David: I gave my girlfriend a boulder fisting for her anniversary present.
Hans: What the fuck man, you literally just obliterated her?!