Billy is one of the main characters of The Grim Adventures of Billy & Mandy. He's a idiotic kid with a very low I.Q. who is friends Mandy and Grim.


  • Billy, along with Mandy and Grim, will join Sonic's team in Sonic Storm Adventures of Billy & Mandy's Big Boogey Adventure.

Ad blocker interference detected!

Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.