You know that thing when you pick up a book, the third in a series you’re getting addicted to. You settle in, snuggle down, start reading and WAIT! What? Your beloved hero is now a brunette, not a blonde. The villain no longer has a limp. The comedy alien now comes from planet zap, not planet zoop. How can the author do this to you? — Well, it’s easily done, but a character bible could have avoided all your grief.