Jen Selter All Greece'd Up In New Bikini Butt Pics

Fitness model Jen Selter has taken her divine derriere to Greece where she posed up in a tiny bikini -- and, praise the booty gods, TMZ Sports has the pics.

Selter has been traveling all over the world lately -- modeling, working out and taking in the sights ... but she found some time in Mykonos to enjoy the beach in a crystal-studded thong bikini.

Fun Fact: there are 4 nude beaches on the island.

Not Fun Fact: Jen Selter didn't go to any of those.