Intro: "The royal family panicked, in disbelief that such a thing could happen." could probably be pared down to, "the royal family panicked." or "the royal family, reeling from the shock, immediately sent..." or something. The former seems a bit clunky!
"to the first adventurer who brings the Princess back..." should be "to the first adventurer who brought the Princess back..." in order to preserve the past tense of the text block. You might also wish to change 100 in this chunk to 'one hundred' to better fit with the rest of the text!
Game: "He approaches you with lewd intention." might work better with "intentions" if only because that's more conventional.
When fighting and losing, 'knocking you unconscious' seems a little redundant. Just saying that the protagonist is defeated should suffice?
First guard's h-scene (not sure if it's different for each character, but I'm playing Rhiannon at this point) "...but he holds you down on him..." doesn't make a tonne of sense! I suppose that it's lingo, but it becomes a little unclear in the sentence. Perhaps, "You groan in protest, but he forces your head back..." or something? Up to interpretation, of course!
"...grabbing you by the hair and withdraws..." should be "grabbing you by the hair and withdrawing," in order to keep parallel structure in the sentence.
Second scene with the high guard: "...gripping what's left of the clothing covering your torso and tearing it from you hastily..." could be, "...(hastily) rips the remnants of clothing hanging from your body..." to make it a bit more concise. You could probably also get rid of 'soft' or 'smooth' in the next sentence, and both describe breasts adequately well on their own! Either that, or replace the 'and' with a comma. "Soft and smooth skin" vs. "Soft, smooth skin" -- I think the latter reads more eloquently!
"...keep your wrists down against the ground..." could be "wrists pinned against the ground" or "wrists pinned behind your head" or even just "wrists pinned back"... though I think you used 'pinned' in the previous text-block, so that might be doubling up too soon?
"...instinctually close your legs..." should be "...instinctively close your legs..." Instinctual is a word by itself, but not with the 'ly' at the end. The one that you're looking for here, and in other places, is 'instinctively'.
"...pushing into you steadily..." could be "steadily pushing into you" and "...he releases a groan full of pleasure as the bandit's..." could probably be reversed so that "the bandit releases a groan of pleasure as his..." just so that it reads with better cadence.
For the gargoyle attack, post-defeat: "...batting away any weapons you might have had away from your reach..." gets quite long-winded. "...batting any weapons from your hands..." or "...batting any weapons out of your reach..." would suffice!
"...and swooping you once more..." is a bit awkward. "...and swooping down atop you..." might work better. Perhaps, "The dark creature manages to gain the upper hand, batting away your/any weapons and swooping down atop you, its claws raking your back..." would be the best way to word the sentence. There are still a lot of comma breaks, but I'm not sure how they could be further condensed without losing the original content.
"...having your bottom garments and panties somehow pulled away," doesn't need the 'somehow'; I think it speaks for itself. There is probably a more elegant word for 'bottom garments', too, though I can see why you would hesitate to specify when you have different characters wearing different articles. Maybe instead of 'bottom' you could use 'lower', as it gets across the same point but doesn't sound quite as weirdly specific?
"...you feel somewhat exposed..." might be an understatement. "Your lower garments and panties are ripped away and, feeling exposed, you struggle back as the creature resumes its screeching, its hard body pressing you down as it mounts you." might be a good way to resolve that sentence. I don't think that the continued references to clawing are needed, as the point is driven across with the first uses.
"...as each forceful thrust it takes into you feels like someone punched you in the stomach, complete with the sensation of breath leaving your lungs..." is also a touch awkward. "You gasp for breath; each forceful thrust feels like a winding punch in the stomach..." might be better.
"You try to crawl forward, in order to grasp some kind of weapon but..." has some comma misappropriation, I think. There are some other bits that could be polished up (har har) into something like, "You try to crawl forward, seeking to grasp a weapon, but you don't make much progress, as the gargoyle is unnaturally strong.
...I think that that's just about everything that I could spot for now. I haven't played through all of the girls, yet, though it seems like they speak little enough to warrant really combing through everything.
This is all nit-pickery, of course, feel free to take it with a grain of salt!