Bully Brothers

The Bully Brothers, or Troublemaker Twins, are two brothers. They first appear in "B is for Bigfoot".

Description
Apparently a few years older than Irwin Pounder, they are predators, which, in human terms, translates to bullies. Scions of an unknown supernatural parent, they are slender and have sandy brown hair and thin faces, and they look to be either fraternal twins, or born very close together. They remind Harry Dresden is reminded of juvenile lions learning to hunt together.

"B is for Bigfoot"
In "B is for Bigfoot", they single out Irwin Pounder as a target for their aggressive behavior, until the moment he reacts and shows them that some prey can be too much for any predator.