Fango, the game is
rugby (like your football, but more fluid and without the body armour!), this game takes place in NZ when an annual international match takes place. The naked guys are fans/players of the game and it grew out of a joke, a few years ago!
This naked match now has a fanbase of its own, the girl (or girls, there have been several over the years) is a spectator or friend of the players and joins in, just for a laugh.
In case you are speaking of a different set of photos, I am totally wrong
