This is a mixed bag if I've ever seen one. There's plenty of promise; I've always liked games where you can choose a loadout of weapons, skills, and special abilities and get through missions in a number of ways. That does create a ton of work for yourself, especially if you're planning to implement an option for a furry version of the main character, too. Is the plan to let the human MC use augmentations/cybernetic enhancements while the furry MC gets a superpower?
There's some teasing at the idea of letting the player corrupt the MC into taking more wicked actions later on. Along with sub/dom versions of sex scenes that's once again setting up a ton of work for yourself. So as not to get buried under scope creep, I'd recommend hashing out and writing the primary branches and throughlines of the story first and then worrying about alternate branches, side character romance &c once you've established your boundaries. Those who end up getting lost in the leaves always make the same mistake: they follow the branches, chasing every little idea they have and letting those expand endlessly while the trunk rots. I've already spotted a few potential trouble spots that suggest those tendencies, like an option to be fuck buddies that ends up not amounting to anything. Save yourself the work. If one of your potential branches is essentially decorative or doesn't end up going in a direction you're interested in, don't be afraid to prune it. Better to let some work go to waste than let it keep demanding more and more of your time.
As for the actual quality of what's there, that's also a mix of ideas that work and ideas that need work. With the sex scenes for instance I found it more funny than hot to see that the go-to move for dominant characters was to tell the submissive character not to move - at all. One character thoroughly using another can work, the facefucking in the bar is an example where it lined up, but more often than not that didn't connect. The main waifubait character for instance is very lovey dovey no matter which disposition she's using, so scenes where she just tells the MC not to move - or he tells her not to move - are in this weird middle ground. They're not cute enough to be romantic or harsh enough to be satisfying 'I've made you my bitch' scenes. The virginally timid dead fish who isn't allowed to contribute to the sex in any way is not a very exciting angle from either end, but it's especially unsexy for a player-submissive character. Follow the impressions that the characters themselves suggest to find better ways to handle this.
I'll stick with the same character to illustrate what I mean: she's very affectionate (giving and receiving), somewhat clingy and insecure, very thirsty, and gets off on both teasing and physically manhandling her partner. Scenes where she doesn't seem to like the main character doing anything to please her - to the point where she insists on doing everything herself - are going against the impressions we're getting from her in every other scene. If we take this portrait and ask what she seems to be looking for, the answers that fit best are passion, appreciation, and reciprocation. In other words she wants a partner who is attracted to her and responds to her advances, but also one who likes and respects her enough to show her as much by taking her seriously, being physically affectionate, and praising her. Most of all, her disposition suggests that she'd really like someone who enjoys (to their own frustration, even, because that's cuter) being tossed around a bit. Put this all together and we get a clear outline for how these scenes should go: lots of physical affection/willingness to please, maybe some body worship, a playfully aggressive/predatory tone (e.g. submissive character tries to take control, she impishly overpowers and teases them like a cat toying with its prey, submissive character gets off to the frustration of the struggle) mixed with notes of tenderness. That also spells out the perfect contrast if you're planning to have a significant focus on jealousy: some other character treating her the exact opposite way and getting a positive response from her would be a strong basis for erotic envy (i.e. 'I can't overpower her like that; what if that's what she really wants?' &c).
You've already come up with a decent variety of NPC-submissive scenes (the bratty deer boy sub was pretty good), so don't let the MC become pigeonholed into this dead end dead fish thing.
Aside from that I'd suggest double-checking some of the choice branches to make sure they maintain a logical coherency. For the most part you were on top of this, but there are a few spots where the stated motives for making a particular decision have no follow up choices that continue or resolve them. Telling Lily that she's moving too quickly for instance is reasoned out sensibly: the MC doesn't know her that well, she came on too strong, &c. When they pick this up the next day, she asks if he's interested in her at all and the only responses are
[No, I don't like you.]
[Ah, what a fool I was! Contrary to everything I told you up til now, I'm entirely ready to make a major commitment to you!]
The awkwardness of the encounter souring the whole thing for him resolves it cleanly enough, but "all my doubts are gone for no reason!" is a pretty wild flip-flop (and the attempt at justifying it was one of the most awkward stretches of dialogue in the game for this very reason). For both the character and the player, the motivation for turning her down the first night could reasonably be summed up as "I haven't made up my mind about you yet". The player likely wants to check all their options first; the character likely wants to get to know her a little better before hopping into bed (and a relationship) with her. We run up against a logical wrinkle where the player and character are essentially forced to take back their previous choice or else turn her down flat. Choices the game doesn't seem to respect or follow through on are going to frustrate players and create a wonky narrative. This wrinkle could be ironed out with a third option to kick the big decision down the road a ways ("let's take things slow" or "let's go on a date first"), giving the player more time to explore what's available and the character more time to logically resolve his reason for not sleeping with her the first night. Whenever you present choices that build on each other like that it's a good idea to go back and reread the reasoning you used to justify it and consider why the player might have chosen that option - as well as what they might want and expect to see as a follow-up to it. Getting these to agree with each other as often as possible will help to hide the seams when jumping from choice to choice and the leash when leading the player along.
There's some teasing at the idea of letting the player corrupt the MC into taking more wicked actions later on. Along with sub/dom versions of sex scenes that's once again setting up a ton of work for yourself. So as not to get buried under scope creep, I'd recommend hashing out and writing the primary branches and throughlines of the story first and then worrying about alternate branches, side character romance &c once you've established your boundaries. Those who end up getting lost in the leaves always make the same mistake: they follow the branches, chasing every little idea they have and letting those expand endlessly while the trunk rots. I've already spotted a few potential trouble spots that suggest those tendencies, like an option to be fuck buddies that ends up not amounting to anything. Save yourself the work. If one of your potential branches is essentially decorative or doesn't end up going in a direction you're interested in, don't be afraid to prune it. Better to let some work go to waste than let it keep demanding more and more of your time.
As for the actual quality of what's there, that's also a mix of ideas that work and ideas that need work. With the sex scenes for instance I found it more funny than hot to see that the go-to move for dominant characters was to tell the submissive character not to move - at all. One character thoroughly using another can work, the facefucking in the bar is an example where it lined up, but more often than not that didn't connect. The main waifubait character for instance is very lovey dovey no matter which disposition she's using, so scenes where she just tells the MC not to move - or he tells her not to move - are in this weird middle ground. They're not cute enough to be romantic or harsh enough to be satisfying 'I've made you my bitch' scenes. The virginally timid dead fish who isn't allowed to contribute to the sex in any way is not a very exciting angle from either end, but it's especially unsexy for a player-submissive character. Follow the impressions that the characters themselves suggest to find better ways to handle this.
I'll stick with the same character to illustrate what I mean: she's very affectionate (giving and receiving), somewhat clingy and insecure, very thirsty, and gets off on both teasing and physically manhandling her partner. Scenes where she doesn't seem to like the main character doing anything to please her - to the point where she insists on doing everything herself - are going against the impressions we're getting from her in every other scene. If we take this portrait and ask what she seems to be looking for, the answers that fit best are passion, appreciation, and reciprocation. In other words she wants a partner who is attracted to her and responds to her advances, but also one who likes and respects her enough to show her as much by taking her seriously, being physically affectionate, and praising her. Most of all, her disposition suggests that she'd really like someone who enjoys (to their own frustration, even, because that's cuter) being tossed around a bit. Put this all together and we get a clear outline for how these scenes should go: lots of physical affection/willingness to please, maybe some body worship, a playfully aggressive/predatory tone (e.g. submissive character tries to take control, she impishly overpowers and teases them like a cat toying with its prey, submissive character gets off to the frustration of the struggle) mixed with notes of tenderness. That also spells out the perfect contrast if you're planning to have a significant focus on jealousy: some other character treating her the exact opposite way and getting a positive response from her would be a strong basis for erotic envy (i.e. 'I can't overpower her like that; what if that's what she really wants?' &c).
You've already come up with a decent variety of NPC-submissive scenes (the bratty deer boy sub was pretty good), so don't let the MC become pigeonholed into this dead end dead fish thing.
Aside from that I'd suggest double-checking some of the choice branches to make sure they maintain a logical coherency. For the most part you were on top of this, but there are a few spots where the stated motives for making a particular decision have no follow up choices that continue or resolve them. Telling Lily that she's moving too quickly for instance is reasoned out sensibly: the MC doesn't know her that well, she came on too strong, &c. When they pick this up the next day, she asks if he's interested in her at all and the only responses are
[No, I don't like you.]
[Ah, what a fool I was! Contrary to everything I told you up til now, I'm entirely ready to make a major commitment to you!]
The awkwardness of the encounter souring the whole thing for him resolves it cleanly enough, but "all my doubts are gone for no reason!" is a pretty wild flip-flop (and the attempt at justifying it was one of the most awkward stretches of dialogue in the game for this very reason). For both the character and the player, the motivation for turning her down the first night could reasonably be summed up as "I haven't made up my mind about you yet". The player likely wants to check all their options first; the character likely wants to get to know her a little better before hopping into bed (and a relationship) with her. We run up against a logical wrinkle where the player and character are essentially forced to take back their previous choice or else turn her down flat. Choices the game doesn't seem to respect or follow through on are going to frustrate players and create a wonky narrative. This wrinkle could be ironed out with a third option to kick the big decision down the road a ways ("let's take things slow" or "let's go on a date first"), giving the player more time to explore what's available and the character more time to logically resolve his reason for not sleeping with her the first night. Whenever you present choices that build on each other like that it's a good idea to go back and reread the reasoning you used to justify it and consider why the player might have chosen that option - as well as what they might want and expect to see as a follow-up to it. Getting these to agree with each other as often as possible will help to hide the seams when jumping from choice to choice and the leash when leading the player along.
