Well, I'm guessing you mean in the game Bioshock since it showed up on the Bioshock wiki's recently asked questions. The sexual themes are all over, in audio tapes and the like, although you have to be familiar with slang to recognize them, and certain buildings in the game like Eve's Garden, which seemed like a strip club to me. Plus, even little things like 'change your sex' which is said by Steinmen technically counts towards the sexual themes tag. If you meant something else, feel free to just erase this.