I realized this as I was typing a reply about the Author being trapped behind the door.
Potential plot hole: Why doesn’t Henry remember the picture of the Author’s door being in his book? August said he’d removed the page from Henry’s book, which sequentially, would’ve been after Henry had already read the book cover to cover at least a dozen times. Unless August was lying again about where he got the illustration of the door, it stands to reason that Henry should’ve seen that image before.
[adrotate group="5"]
"That’s how you know you’ve really got a home. When you leave it, there’s this feeling that you can’t shake. You just miss it." Neal Cassidy