Sorry if the following is already known to you, but I wanted to mention it if not: It is still possible to redeem Steam keys for adult games in Germany and itch.io is to my knowledge the only bigger shop where such keys can be bought directly from creators. I totally respect your choice to not include a key for another platform for sales on here, but I‘m always glad if I can add a game to my Steam library and let it handle updates. And Steam achievements are nice as well, even though you have implemented a really great in-game gallery 😉 Good luck with your game and best regards from Germany 😊