Alright, I'm going to be a bit more critical than most of the other reviews here, but before I get into it I just want to make clear that while this entry didn't really land for me, it's nothing personal and getting any completed jam submission, especially your first, is a huge accomplishment that you should be proud of. With that said, I'm going to go ahead and break it down.
Implementation of Theme:
Yeah, it's there, and you definitely attempt to call attention to it by specifically referencing the word "folklore" several times in the script. My only issue here is that while yes, there is in-universe folklore about Rook and maybe some of the other monsters and phenomena in the game universe, on a meta level that "folklore" was only created by Alden to be a thinly veiled metaphor for the MC's absence from the group. I'm good with artificial folklore, including within the scope of a game universe, but this feels less integral to the universe and more just like a plot device, both in the party's campaign and in the VN itself. I think it still counts, so I'm giving you credit for it, but I think the theme was more deftly handled in some of the other entries I've read so far.
The line "[A story] becomes dangerous when people remember only the frightening parts" goes pretty hard though.
Writing:
Alright, let me preface this section by stating that I'm not accusing you of anything, I'm just making an observation and recounting my reaction when reading the VN. When I read the sentence "The house smells like rain on wool, old paper, and something cinnamon-sweet cooling in the kitchen." my heart sank a bit because that structure (e.g., smells like [x], [y], and something [z]), especially with the fixation on scent where it doesn't really need to be there, is something I've seen very often in AI-generated prose. The negation structure that Pink pointed out in their comment (e.g., Not [x]. Not [y]. Just [z]) is similarly common, as is a general over-reliance on metaphor. I'm giving the benefit of the doubt here, but I'm also flagging this as something to watch out for as you refine your style.
With that said, as others like Pink and Cardigan mentioned, AI scares notwithstanding, excessive similes/metaphors and repeated syntax is something you want to avoid since it can get pretty tedious to read. Figures of speech and unique syntax can be very effective, but the more often you use them, the faster the effect wears off. It's not only okay, but advisable to space out those flourishes to let the imagery they convey breathe.
Presentation:
Presentation here was pretty solid for the most part. There's no penalty for using the stock assets (that's what they're there for) and I think expressions were handled to the best you could expect using said stock assets. I think the UI and menus also fit the vibe of the VN, and the music generally worked, though I wish there were some sound effects or more variety of tracks within individual scenes. Tracks can continue uninterrupted for sometimes like two full chapters at a time, which can get a bit repetitive.
I think the MC for this story also definitely needs to have a name, even if you have the player enter their own to keep the "blank slate" idea. More than anything else, you need a way to distinguish when the MC is speaking as opposed to just narrating since both cases look exactly the same in the text box. Especially if a reader is rapidly clicking through, which they very likely could be due to the repeated staccato syntax, it can be easy to miss dialogue buried at the end of an internal monologue.
There were very few proofreading errors, which is great to see, though, just from personal preference, at least for a jam entry I wouldn't mind exchanging some typos for freer flowing prose.
Story/Creativity:
So, I know you were, at least to some extent, going for vagueness in the plot and inciting events to allow for flexibility in your "blank slate" protagonist, but I question how effective this choice is. All the characters here are basically one-note: Bran/Caelan is the brawny and courageous one; Mira/Sable is the snarky (sometimes) and sneaky one; Nico/Quill is the cautious/quippy/nervous one; and Alden is the DM (I really can't think of any other distinguishing personality traits for him besides "nice" and "presumably likes the MC"). The MC themself has no traits, basically at all, other than having friends and not playing D&D for a while for an undisclosed reason (at least initially).
I read another entry for this jam a few days ago that dealt with very similar themes, like growing disconnected from friends that you played a specific nerdy game with and the uncertainty and insecurity that comes from that. While I had plenty of issues with that story's focus and pacing, the characters were really fleshed out, with developed, unique personalities, and the game world they inhabited was similarly detailed. It felt like that game universe existed outside the immediate plot. The effect of all that was that the story felt real. The characters and their interactions felt real.
By contrast, this story just feels a bit generic to me. Sure, you can graft your own experiences onto the text, but the text should be helping out with at least some of the lift. As it is, I found it difficult to get invested in resolving a conflict that was mostly undefined with characters that were similarly mostly undefined.
This might also be personal preference, and my own brand of social awkwardness not necessarily aligning with the creator's or the characters', but I'm not sure how I'd feel about my friend creating a whole campaign that revolved around asking me why I stopped hanging out with them. Like... I see what you're going for, but I feel like that would make me pretty unnerved and maybe a bit frustrated that they had to set up a whole event instead of just asking directly. Again, maybe a personal thing there.
Overall, I think there are some really interesting ideas here, but I think they need to be expanded on and filled out to really stick. It's not a bad first effort at all though, and clearly many readers were more receptive than me, so regardless of any feedback you receive I hope you stick with it and keep writing.
Final score of 2 bags of Flamin' Hot Cheetos out of 24 cans of Mountain Dew Code Red.