Girl Who Cried Monster, The (Goosebumps Presents #1) by R.L. Stine - Vintage Paperback

"Do you like monsters? I do. I love telling monster stories. Especially to my little brother, Randy. He's a total scaredy-cat. But now I have a little problem.

"See, it all started when I went to the library. That's where I met Mr. Mortman. He's a really creepy librarian. And one night, after the library closed, I saw Mr. Mortman eat a whole bowl of tarantulas for dinner! That's right, he's a real live monster. And now he's after me... for dessert!"
—Lucy Dark