I didn't want to say anything before since I felt like it would be complaining about the lack of apples in an orange orchard, but have you noticed that most games on this site are either Visual Novels, Kinetic Novels, or are otherwise extremely simplistic? They're all popular here because the character art is attractive. This is no exception. If you're impressed by visuals and don't care for the game part, that's fine.
However, the actual game is dreadfully boring and grind focused. I use console commands every single time I touch this game because there's not much to do after you've seen each progression step's scene. The actual training is has little input. No worrying about preferences or tactics or even cleaning your girls. All you have to worry about is buying an outfit every blue moon, maybe visit the lab after a girl's already a raving slut, and waiting for the corruption meter to rise. This is compounded by only having one girl to train at any time and only being able to unlock them in a specified order. In fact having a linear story structure in a format thats all about branching and looping baffles me to no end. as for their other games, Raven's Quest suffered from long moments of nothing happening as well, and I never bothered with The Wind's Desciple since I saw "slow and dedicated evolution" and noped out.
All that said, Iono is the main reason I'm still checking updates as she's the only one who's body and fetishes I'm attracted to. If Imp Midna from Twighlight Princess showed up for example I'd likely have more kind words to share. However I suspect Patreon is one report away from nuking the game specifically because of Iono's beast attraction. It's unfair that everything I like is hated by these chooks.