Here's an interesting observation:
Men can achieve orgasm through anal stimulation, because of the positioning of the prostate. Women usually can't achieve orgasm through anal stimulation (exceptions exist) because, well, they don't have prostates.
Conversely, women can achieve orgasms without penetration (well, duh).
What does this tell us? It tells us that God has actually equipped men to be able to enjoy both aspects of anal sex. It also tells us that God has equipped women to be able to enjoy non-penetrative sex, as in, sex where no penis is involved.
Conclusion: If Intelligent Design is indeed true, God has purposefully equipped humans with features that serve no other purpose other than making it possible to have gay sex.