"In. Not Unlike Errol." is a red text modifier on weapons in Borderlands 2 Harry Potter reference bro.
Found on the following red text weapon: Sapping Sand Hawk, (or any other version of the Sand Hawk SMGs) which is a mission reward for Captain Scarlett's mission "Whoops". (Requires: Captain Scarlett and Her Pirate's Booty DLC)
Grants Weapon Effects
The Bullets fired from this weapon form the shape of a bird flapping its wings