Bud & Lou

Bud and Lou are the pet hyenas of Harley Quinn, named after the comedy duo Bud Abbott and Lou Costello.

Though initially owned by the Joker who used them to help him fight Batman, the two hyenas bonded mostly with Harley and left with her after the couple's breakup because she was usually the one who fed them. Whenever their owners were sent to Arkham Asylum, Bud and Lou were usually taken to Gotham Zoo.