I'm gonna try and give some actual good criticism instead of just saying "this sucks" or "this is amazing", First I will note the negative and secondly I will note the things I like
The major bad thing that affects many games similar to this is a bunch of filler text, pretty much text that add nothing to the story or to help the player, I'll give some examples from the game
1. When creating your character just before you put in your carrying capacity (which can also be shortened to carry weight) there is a wall of text that can simply be shortened to something similar to "Enter your carry weight (in kg) the human average is 20kg if less you can train at Outset Town before reaching around there, carry weight may also change due to curses or exercising" it get's what you want to say across without wasting time
2.Another one is explaining the companions, you even added a short version which is nice but it also misses some things about them, since we are still in the tutorial/learning there is no point in adding a bunch of random things that don't help just to add words, you could just explain what they do and add a little bit of "lore" or details
There are a lot more but I'm trying to be direct with it. What I'm trying to say is a lot and I mean A LOT of things could be put in lesser words and get the message across while being short and detailed, I'm gonna try and give an example by writing some random shit
(Too Long) "her legs where immaculate, the most stunning beautiful things I've ever seen, when I saw them I wanted nothing more than to just lay my head and fall asleep between them, they were as comfortable as clouds and made my face feel like it was buried in heaven by how soft they were, and as I fall asleep she comforts me by singing with the most euphonious voice I've ever heard, and as her gentle lovely fingers comb through my hair I fall into a deep slumber dreaming of nothing more than spending the rest of my life with such a beautiful woman that has brought nothing but amazement to me"
(Too Short) "She had beautiful legs, and as I lay down on them I fall asleep while she sings and I dream of our future"
(About Right) "I lay down on her majestic pair of legs and am overjoyed on how soft they are. As I fall asleep I start to hear her melodic voice sing to me, and as she brushes my hair with her fingers I think of the wonderful life the future holds for us"
So what I'm trying to say is don't try too hard to add every single detail about things, leave some for peoples imagination, you can add detail but also keep it clean and simple, like the saying goes LESS IS MORE. A lot of games similar to this have the same issue, its like a college student that has a 800 word essay due in 5 hours so they add a bunch of shit that adds nothing lol.
Ok I know the game is new and I'm pretty sure you are working solo so I won't be too harsh. You seem to be focusing and adding a lot of fetish content while sex is pretty much a super rare thing, most of the curses are sexually related but sex is rare to happen. Adding More curses that affect the overall survival of the player could make the game more interesting. Another thing that I mentioned before is sex is pretty rare, I don't mind it having you sort of "work" to get it instead of being click here and done, matter a fact I prefer that, but then again sex is pretty rare to happen even though there are so many things that affect it. Also a lot of the time the game feels very very repetitive, I mean I could basically go down however far I want without much problems, I think that adding "Activities" like puzzles, fights, or quests before being able to descend would help a great amount, that is another thing I wanted to talk about, there is a gun and a sword but the combat I've seen has just been click once and done. Adding some form of actual combat could make the game a lot more fun.
Also there needs to be a lot more visuals, animations or just pictures, you seem to not care about using AI images so you have infinite potential with them, so take advantage of that
Now for the good things
The major good thing is you seem to actually give feedback to what people have to say and what you plan on doing, interacting with people is a major part of creating a game so good job on that.
You seem to be finishing the things you already have in the game, like adding curses and relics instead of leaving them bare bones, however just don't focus too hard on just finishing what you have, add new things (like combat I really do mean it)
The story and overall setting of the is well done, while obviously being inspired by Made in Abyss you added your own twist and it seems to work, the story is nice the Idea of what you are doing sounds fun and honestly this could work really well and I do see it being pretty popular as long as you keep on going. So nice job
TLDR: The Idea is great and has a lot of potential, you are very good with interacting with people, the writing is pretty good, BUUUUUT....... STOP ADDING SO MUCH FILLER TEXT, add new things to do like combat and puzzles, make sex more common, make curses less sex related and more survival related, start adding more images or animations (ai or not)
I hope this helps in some way I know I typed a bunch even though I told you not to do that lol, but I'm just trying to help, good luck and I hope you have fun in the project