Attila is Ms. Lips's pet catfish. He is mean and envious.
When Bea came to Ms. Lips's house, she was told to babysit while Ms. Lips was gone. Bea thought Ms. Lips had a baby, although it turned out that Ms. Lips wanted Bea to babysit her pet catfish, Attila. Bea brang Oscar and Milo to help, so the moment Ms. Lips came out of the door, they had to somehow babysit Attila. Milo liked Attila, saying he's "amazing". He regretted it after Attila attacked him. Oscar was allergic to catfish, so that didn't help the babysitting job easier either. After feeding Attila, Bea later decided to quickly stop at the Burger Bunny. When they got back, Attila disappeared. It turned out he went to Freshwater High to look for Ms. Lips. Bea tried to convince Attila to go back to Ms. Lips's house, although he attacked her. Bea figured out that Attila hates everyone except Ms. Lips. So Bea dressed up as her, which fooled Attila. Bea and Oscar eventually brang Attila home, with Ms. Lips in the house thinking that Milo (who's disguised as Attila to fool Ms. Lips for a while) is Attila ("Adventures in Fish-Sitting").