Little Monster

Little Monster is the main character of Mercer Mayer's Little Monster books, especially the Little Monster: Private Eye sub-series. In the latter, he is a chief inspector and is accompanied by Detective Kerploppis (spelling may be changed later). In either series, he is a juvenile monster in Monsterville. Besides parents, he has an unnamed older sister, an unnamed baby brother, an unnamed dog-like monster for one pet, and a Zipper-umpa-Zoo for another.

In Little Monster at School, both the book and Living Books' computer game adaptation, he is a good friend to Yally, as shown when he helps him with his letters.

In the Little Monster: Private Eye series, he is the inspector and solves particular crimes.

For example, in the "Smelly Mystery" story, he and his assistant have to solve the crime of the Evil Smell-Switcher, where, like everybody else at the sleepover, he was a suspect because he was there then, but he is never the perpetrator. When he and his assistant are looking for clues, they get every other boy at Yallapappus Manor (Yally Yallapappus's house, where they had the sleepover) to reveal the perpetrator who then tries to get away, only to end up in a trap. Little Monster questions the villain's motive. When he admits the reason, Little Monster gives him feedback, and his assistant agrees. When the villain wonders if he is going to call the police on him, he says no, but instead, in fact, even worse, they will call his mother.

He is voiced by Aaron Schlichting in the Living Books adaptation of "Little Monster at School" and DeAngelo in the Big Tuna adaptation of "The Smelly Mystery."