Here are two books about monsters that we found through some library visits and enjoyed reading (and which I find very clever and fun):
"Dark Night" by Dorothee de Monfreid, is a cute story about how Felix, the little boy, escapes from some woods filled with ferocious beasts. (My son laughed so hard he lost his breath the first few times we read this!).
"Leonardo the Terrible Monster" by Mo Willems, puts a spin on what it means to be a terrible monster.