In it, a little boy is accused of tracking mud through the house. He claims that it wasn't him, but rather a green troll-like creature named Disgusting McGrossface.
The bulk of the book is rhymes about Disgusting McGrossface and his alleged gross appearance and habits.
Disgusting McGrossface provides examples of
- Cartoon Creature: Disgusting McGrossface is a humanoid creature with large ears and green skin. There's also several other weird-looking creatures in the police sketch.
- Cyclops: A one-eyed creature can be seen on the police sketch.
- Does Not Like Shoes: Disgusting McGrossface is illustrated without shoes.
- Eat Dirt, Cheap: Apparently, Disgusting McGrossface "brings in mud, then licks his feet dry".
- Extra Eyes: On the police sketch, a creature with nine eyes can be seen.
- Extreme Omnivore: Disgusting McGrossface licks mud off his feet and eats worms with every meal.
- Invented Individual: It turns out that Disgusting McGrossface was completely made up and the boy did track mud through the house after all.
- Kid Detective: At the end, the boy holds up a magnifying glass and promises to look for clues. Subverted as it turns out that's just part of an act to hide the fact that he was the one who left mud in the hallway.
- Meaningful Name: Disgusting McGrossface is just as grungy as his name would suggest.
- Name-Face Name: The titular character is called Disgusting McGrossface.
- Name McAdjective: The titular character's name, Disgusting McGrossface, has the pattern "[adjective] Mc[adjective][body part]."
- Nose Nuggets: Disgusting McGrossface is said to have a collection of used tissues and uses his boogers to hang things on the wall.
- Peeve Goblins: Disgusting McGrossface is said to be the one who left the mud in the house. Subverted as it was actually the boy who did it.
- The Pig-Pen: Disgusting McGrossface is said to not bathe in weeks, doesn't brush his teeth, leaves his dirty underwear on the floor
- Suspiciously Specific Denial: The boy says that Disgusting McGrossface was the one to leave the mess "no doubt, for sure".
- Toilet Humour: The whole book is listing a whole lot of yucky habits a creature has, such as keeping used tissues and licking mud off his feet.
- Unusual Pets for Unusual People: Disgusting McGrossface keeps a pet rat, which is supposed to be indicative of his gross habits.
- You Need a Breath Mint: The boy calls out Disgusting McGrossface's bad breath by saying, "Ever heard of toothpaste?".