To manta ray someone, you must catch them off guard, usually after somebody goats/bulldogs you....
You casually smile and say " you ever seen a mantaray"
and then with two hands grab the foreskin of your balls and fold them over your dick all the way up to your pant line or even belly button...
Note: few can actually pull of the manta ray. Very large balls are necessary
Andrew: dude, Mike passed out cold
Moses: I should teabag him and send it to his mom
Charles: ....or I could give him the manta ray
Something that must be poached!
Look at that small wane Manta Ray! Hey Ray Sipe go poach em!