To the female protagonist haters in this thread; Here is my perspective on female protagonists
I am a dude, straight as they come actually. But I pretty much only enjoy adult (sex) games if they have a female protagonist.
On the other hand, a visual novel, an anime, or pretty much any non-adult media I will play/watch only as a male protagonist, this is because I like to roleplay these types of games and as a straight male I need a straight male protagonist to roleplay as. (Note while VNs have sex scenes, they are an aside, if we are talking Japanese VN's I tend to avoid Nukige unless it actually has a good story).
I can only assume your hate for a female lead is that you also like to roleplay your protagonist, but as you are male you cannot roleplay a female (which is fair enough)?
So, why a female protagonist in full H-Games? Well I kinda like seeing heavy shit happen to the females (not like disturbing heavy, but heavy), if that female is the protagonist and/or not responsible for the "heavy shit", I dont have to feel guilty, I am just an observing party, I do not like to roleplay as a male who is a total dick. If the protagonist is a female, I kind of go into observer mode, not roleplay mode. The games with a male protagonist And heavy stuff, tend to be NTR games, or r$pist bastard male protagonist games, both of which, I hate.
Other games with a male protagonist tend to just involve fucking aload of women in (imo) fairly boring circumstances. The female protagonist opens up more interesting situations (again imo).
If the protagonist is female I can watch some of these heavier themes (such as blackmail, r$pe, drugging etc) occur without trying to roleplay someone I hate that is doing all of this, and without being NTRd The female lead just provides a PoV not a roleplay point. Note: If it is a female protag, it is not really NTR, just cheating (and it is generally because of blackmail or something, atleast to begin with), and any mushy bs with the boyfriend such as in, "Anna Exciting Affection" or "Lida's Adventures", I would just skip.
It is fair to say, games when a female protagonist is just a total slut from start to finish and goes around sleeping with men for fun I also avoid.
I would also say that a female protagonist can be decent for lesbian scenes. Plus, particularly in RPGM games you have the added bonus of constant eye candy of the protagonist, rather than some gross male protagonist =/.
I have thought a reasonable bit myself as to why the heck I prefer female protagonist games (as I was kinda surprised myself when I realized I preferred them lol) and this is those thoughts on "paper".
TLDR: It provides a way to present some interesting fetishes without having to roleplay as a r$pist bastard male lead or get NTRd.
Note: Obviously not everyone will have the same reasons as me for enjoying games with a female protagonist. But this is a viewpoint of a regular guy which I think explains the rationale behind paying a game with a female protagonist fairly well.