Right, I hate for my first feedback regarding the game to be criticism, but since I have nothing else to complain about (game's very good otherwise), I will lay it out here. I don't understand the point of including the plot point of elves being able to transform into succubi. I really don't. Especially in the case of Bessie. You already have a good character, you already have a character that is sexy enough, why do you have to railroad them into the most common monstergirl stereotype for no apparent reason while creating dubious worldbuilding implications? Just why?
I like the story overall, I like the character development work that has gone into it, but this just seems unnecessary. I don't want to impose too much, I know it is hard enough writing a good story to begin with, but I would appreciate if at least her becoming a succubus later on (which is where this all is inevitably driving towards) was optional.
Is the criticism here that succubi are overdone, or that you don't like the fact that elves are ancestors of succubi?
I'm finding it hard to understand why either thing is bad.
Something that is overdone isn't necessarily a bad thing, and having a certain fantasy species being related to another by blood in a unique fantasy world is a preference at best.
In my world, elves are related to succubi, goblins are related to imps, fairies are related to pixies + nymphs, and much more. These aren't particularly important plot points.
It seems somewhat unusual to me that you seem to say succubi are the most "common", while your other criticism seems to be that I chose not to "railroad" elves into their most common fictional representation by giving them a unique twist.
To me, and I may be wrong, but it sounds like you dislike the concept succubi. If I were you, I imagine I'd have made plenty of decisions differently to better suit your tastes. Unfortunately, I'm just a single person stumbling around the world like any other, and I can't anticipate any factors that might personally not suit your tastes.
If it's any consolation. You have expectations of what "elves" and "succubi" should be, but if I had called them "Elheim" and "Saddarah" you probably wouldn't have had any complaints, right? In the same manner your expectations regarding elves appears to have been subverted, your expectations around succubi may be as well. Bessie is Bessie, she'll be an ever-loving and loyal elf until the end.