So I played the game, and since the dev is active here I thought I'd share my 2 cents and maybe inspire some improvements.
First off, kudos for the art. I know it is quite controversial atm to have AI CG, but imo this looks pretty good and stays pretty consistent trough the different levels for each girl.
My biggest issue with the game however is the gameplay, as there is pratically none to speak of at the moment. BUT there is a
lot of potential here.
The current gameplay loop is: Peek and Choice, possibly watch a PNG change. Repeat. There is no difficulty increase, or thinking required from the player at all. The image changing needs to be the reward that the player gets from playing the game, right now however, it is just a chore.
This is how I personally would change the game:
Have one "turn" be one week. The player could then choose a girl to spy on for that week. The player would then get information about that girl that they can use later. That girl would now no longer be available that month for she would become too suspicious of the player. The player would then be able to choose other girls to learn more about. This information would then be added to the profile we are building of that girl. Aprofile the player could see whenever they liked.
To also break down the grind a bit, add a mini-game or something that challenges the player when spying on the girl. Maybe the player needs to look at the girl when she is not looking, like a red light green light type of game. This could also become more difficult when the level of the girl increases. Spying on her in more compromising scenarios or something that would increase the tension when playing the game. Maybe shorter periodes of time before she looks your way again. Or maybe a bf or husband that will also be present and has to be avoided. The upgrades that you are able to buy would then help you in this game somehow. Maybe creating a distracting or having more time to spy on her. Also make it possible to fail this game. This would create more tension and fun when playing it.
I would then have the player choose a girl to "level up", this would be done by some sort of quiz about the information we found out about the girl when spying on her. This information could maybe even be found when spying on her, something to click on and collect when spying on her. When the player succeeds this quiz, the girl levels up and the player is rewarded with some titties. And each time she levels up the quiz gets harder: less time, more questions, more things that the player needs to know about the girl. And the player is rewarded with a lewder image of the girl. And each girl could have a unique reason as how/why the quiz is happening. This would create more uniqueness around each girl, instead of just their looks.
Also have some extra thing when I max a girl out. She becomes my girlfriend and I now have access to some x-rated images. Something to reward the player for maxing her out.
But that is just my 2 cents, I am not the dev and they can do with the game whatever they like. This is just something that I think would improve the game. If you are the dev and reading this, do with this what you please
Oh and P.S have some setting for female and male prefrence. I'm straight and I would like it to stay that way thank you very much