What I'd like to see is a plugin that makes books placeable in the physical Minecraft world. I want players to be able to enter houses, see a book on the table and right-click it and be able to read it (but there should be some sort of permission that prevents them from being able to take it into their inventory). Hopefully this isn't too hard to do, I'd be grateful for anything that's better than having them right-click a sign, which just seems weird to me... Thanks in advance!
You can't do unplaceable things that isn't blocks placeable. Maybe place bookcase and left click to read it. Not placeable books.
You could spawn item showcase like showcase plugin does and make it so if you click the block the fake book is floating on, the book will open as if right clicked from the inventory and let the players read it.
