Junior Fiction/ YA chapter book. Creepy. Squid or tentacles on cover coming out of a door.
I read this book in primary school year 6 Australia (2014) I just remember the cover being dark ish and having a door with some light coming out and something coming out. I’ve tried remembering with a friend who also read. She remembers the story being about ghosts and creepy things.
It is not - All the lovely bad ones