I like the art and the story and the concept as a whole... enough to think it a real shame that the sex scenes, if you can call them that, are close to the least erotic thing I've ever seen. If I look I can probably find actual spreadsheets that are more arousing. It's one thing if a dry numbers game is applied to simulated combat, but I think it's really off-putting when it's used to describe the outcome of sexual encounters (especially when terms like "damage" are lifted wholesale). This is a shame because, to me, it ruins what would otherwise be something interesting and unusual (well, less usual than most of the games anyway).
If the "combat" isn't going to be reworked entirely (and I'm realistic enough to know that it probably isn't going to be), at least consider layering something over it that hides the dry, clinical exactness in favor of something more engaging and/or reduces the length of each encounter to de-emphasize the mechanical nature. For example, you could chop at least 2 digits off every number, add named buckets ("strong/high/powerful" rather than just "72.65"), and remove exceedingly unsexy words like "commit", "target", "damage" and "cancel". This layer can be an option if necessary, I'm not out to ruin the fun of the min-maxers (although I should think they have plenty of games to scratch their itch already...) And no, this isn't the same as easy mode -- the issue is immersion, not difficulty.
I can only speak for myself, but I can immerse myself far more with "oh I guess I wasn't nice enough to her yet" rather than "ah I see my seduction stat is 2.34 units too low on average, I shall click this button here 5 times, which should fix it -- ah yes yes, now my number is bigger than yours indeed, you shall be royally boned, and by that I mean my lust damage increases" -- even if the actual mechanics are the same under water. Somewhere between a "pick A or B" kind of interactive story and a hard number-crunching simulator must be some sort of happier mean than what the game is currently offering.
Even without changing the system at all there's probably low-hanging fruit that could increase immersion without removing the min-maxy stuff. A description like "The gentle Leirien masturbated Mir's breasts. Padmiri received 2.00 lust damage" offers the worst of both worlds -- using three different ways to describe the same person in one passage is something a novice writer would do because they've been told repetition is bad, and then that's married to the unsexy outcome of lust damage. Even without changing the numbers at all, this could become "Padmiri masturbates her breasts. [Mir: -2.00 lust]" -- i.e. make the descriptions as natural as possible, even if the code has to be more involved to do this, and separate the mechanics so they don't disrupt the narrative. A second person option would also be nice -- don't call me, the player, by my name in scenes, as this removes me from the action; using "you" and "your" and "myself" is fine (I say option because I can imagine other people prefer third person, the weirdos).
OK, long post and it looks pretty critical now that I reread it but it all comes from a place of love, I promise.
Edit: "lust" seems to be the wrong way around in any case -- it should start at 0 and increase to a cap as lustful things are done, instead of starting high and getting "damaged", leading to a climax when it's 0 (no lust?) The rigid mechanics are really showing there, it reminds me of THAC0 instead of armor.