I selected none, and here's basically why:
Time/Universe Travel - If I had to pick one of the three with no other options available, this one would be the one I would probably pick... The trouble is that I've really not read/played many Erotic/Adult Visual Novel/Games, using this theme, that were any good and/or had a well put together story... Usually they are porn fests with stereotyped/over the top characters... Or they are porn fest grinders, with not a whole lot of story... Or the story had ridiculous plot usage... Or there were attempts at humor that I didn't find all that funny... It's really a theme, I've not seen used very well, or it hasn't resulted in anything all that immersive and/or fun to read/play...
Sci-Fi RPG/Strategy - I really don't see myself enjoying an Erotic/Adult themed strategy game of any type, let alone sci-fi... As to RPG, that all really depends on the VN/Game style... Normal RPG games come in a myriad of game styles... And that makes it too vague to really know if Erotic/Adult themes could be used that well… Just depends...
RPG Monster Battle - First off, I'm not into Monster sex at all... It's too close to being bestiality and has a tendency to include nonsense like Tentacle sex and stuff like that, most of the time... Plus, there have already been lots of attempts at Monster Battle games and Pokémon themed games in this market already... And I pretty much avoid them all...
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