I just finished Moss, and then went back to get a single scroll collectible (whatever they're called) I had missed, to complete the game 100% ... except that I still don't have the final, secret achievement, and haven't unlocked Quill as a Home decoration (I'm assuming the two are related).
Looking online, the only achievement I don't have is... ironically, the achievement for getting every other achievement. Is it bugged, if you don't get them in a certain order or something? And does anyone know a way to get it to trigger?
I really wanted to place an adorable little Quill somewhere in my Home. And although none of us really count achievements, I was looking forward to having a game at 100% lol.
It's hard being the voice of reason when you're surrounded by unreasonable people.