Let's start with the obvious; this is a converted video game from a Made in Abyss CYOA. The game uses audio files from the original Made in Abyss, and only a few pieces of artwork. Otherwise, it is its own entity, so don't get your hopes up expecting a certain MiA character to show up or something.
The game is skeletal right now, but the transformation, curse, corruption look works pretty good. If you're just into seeing characters go through transformative changes and using that 'curse' to get different visual changes, then this is for you.
Eventually the hope is that this becomes a fully fleshed-out game, or at least enough content to keep playing for a few hours more, in the next few updates.
Right now it's very barebones, but the promise in this is genuinely exciting; the only other kind of games like this are either abandoned, or stuck in dev hell. Here's hoping this one does better.