Harry Potter is evil? Or are people just stupid?

Hey! I'm a Christian and I love the Harry Potter series and I've been getting a lot of crap from church members and my mom. I don't get it, it's just a book and its a good book too. It all started because me and my friend are planning on going to the theme park in Universal. My moms like you're becoming a devil worshiper and threw majority of my Harry Potter stuff away. WTF? Do you think it's evil?