Done naked, post rugby game, opponents welcome. One arm under your crotch gripping your mates hand similarly placed, your other arm gripping
the dudes hand in front of you. Singing
something like "We all going on a Lion Hunt".
All the rest is bogus. Sphincters, dick grabbing etc., are knock offs by twits if they exist at all.
Best done at the bar or
the Common Area if it's late enough.