the problem with games like these with money is that you often will just eventually have so much of it that there is no issue with anything you possibly want to do, like when I played Futa dom world money was very easy to min max and I had easily a couple thousand in roughly a ingame week which made raising stats super easy. But you also can't make currency to hard to get so unfortunatly unless theres another use for the money it might as well not be a feature. The problem with money in games is finding a balance between being far to important where you might as well be playing a tycoon game or just completely useless. Which is where a tax system comes into play, it could perhaps be a percentage as to encourage players to keep earning money while never having to much of it to make it useless, thus forcing you to balance the tax and your rent money with other things. which honestly could easily be fixed by having the easiest difficultly not have tax, normal a small tax, and hard perhaps having a moderately high tax?
Also I see, I guess it makes sense to have a succubus power system since the MC is now a semen demon who is powered by semen lol.