To mank someone, it is a verb meaning having sex with a girl who is so short/light that you are able to convieniently pick her up as you do it. "Manking" has become a new way to have sex with short girls while standing up, and has created new oppurtunities for multitasking during sex.
Dude, that girl's ass is sooo hot; I just wanna mank the shit out of her.
Dude, I heard your little sister got manked!
"Where's Mark?" I heard he's manking that girl from his science class."