Turns out that the boo word has a lot of meanings. It can mean someone you love or care about. Also, it can be someone who is a lifetime best friend or who is always there for you. Someone who is extremely pretty or important in your life. Someone who can make you laugh. Someone who you can never replace. Or a small spherically shaped ghost that is only visible when your back is turned. The last one perfectly describes our fanart Boo Sticker.