Survival Island (2002)

Not to be confused with the 2005 film of the same name starring your friend Billy Zane, Survival Island (2002) stars Jaime Pressly and Buffy's Nicholas Brendon as two of a group of young people stranded on a tropical island. Honestly, getting stranded on a desert island is bad enough, but the plot quite literally thickens when they discover that a piñata they found on the island is actually inhabited by an ancient demon that wants their souls! 

While the plot of the film is preposterous, it's not unreasonable to expect plenty of bare flesh as these randy coeds get their rocks off. Unfortunately, the sex never really materializes, but we do get to see Aeryk Egan's bare ass when he moons his friends on a boat! No man's ass is an island, especially not Aeryk's!