The tiny little bug lives in all types of stone throughout the Overworld and the End. This bug burrows through rock and eats them, but they prefer the shiny Ender crystals in the deep End. That's why most of the Ender crystals mined have holes in them. Even the Endermans hate them. They usually leave some bits of crystals on their body, which had sprouted into mini crystals over time.

Warning: BE CAREFUL OF THESE BUGS WHEN MINING FOR ENDER CRYSTALS OR STONE. They may swarm you up (Endermans may get swarmed too) and cover you entirely while biting you. They can duplicate themselves (WTF?!) to increase the number of bugs... Horrible...