Spoilers included
Goodness gracious, that was quite the surprise. I really wasn't expecting that ending, though I did have my suspicions about the narrator being their own character. I really enjoyed this work. You wrote in your note that the mermaid was the weakest storyline, but I still liked it quite a bit. Her backstory wasn't as fleshed out as the gravedigger's, and her character wasn't as pronounced as the princess's, but the death depicted in her ending was so visceral I think it will stick with me for a long time. I was also fond of the witch. Knowing the story is written from her perspective really changes things. The fact that the protagonist never had her own dialogue and that the narrator, who was quite opinionated, would occasionally speak in first-person did not escape me.
The use of choices rather than a text box being used for Rosette's dialogue really made it feel as if she had become her own person. Her and Meada being the only named characters further solidified the feeling of being alone, with the other characters being nothing more than puppets on a string.
I also find the uniform Rosette wears to be quite interesting, as well as the mentions that she is "not from this world". This seems to reference the fact that she is in a created world. I believe she may come from one that's similar to ours. However, the mentions of her being well-bred and seemingly implied to be a noble make this a bit unclear. Of course, those statements don't actually come from her, do they?
The point of the matter is I enjoyed this game. The writing was phenomenal, the art was pleasing, and the real-life photos were edited in a way that didn't clash with it. Not to mention the music and the textbox details (maybe it's odd to point out, but I really did enjoy the textbox, especially the button sounds); all in all, it makes for a brilliant and immersive experience.