The reason why there's so little of it is because this is a game that's on Steam for $4usd. There's supposed to be more girls in future updates.
Gameplay TLDR: It's a match 3 game with a small but neat JRPG twist. It does feel grindy at first but then you'll realize that there's a very mysterious "item" in the shop that requires a bit of "outside research."
They're also apparently on patreon found here: https://www.patreon.com/GinkgoStudio
I personally think that this is worth the $4usd, its gameplay is far more polished than any other H game on Steam because of one simple reason: the devs remembered that they were making a game and not just an artbook with Bejeweled/Candy Crush slapped in it. For a small project with that much polish, how could you not give the game a shot?