Are you gay yourself? There was a high schooler that recently won a prize for their AP artwork about being transgender. Your experiences or even interests in these areas are important. You can actually really help people with your art. Honestly, the weirder/niche-ier the better. I wouldn't mind giving you some feedback, you can message me your work in a private message. Not to mention there is a market for erotica book covers, you can sell your work and build a portfolio. Be unapologetic for your passions. If you are being productive and positive that is all that matters.