We think we saw Hugo at the airport; he was boarding a plane to Switzerland and.

Related:

• Homer: We chained Hugo up in the attic like an animal and fed him a bucket of fish heads once a week.
  Marge: It saved out marriage! Treehouse of Horror...
• Bart: Who or what is Hugo? Marge: Hmm. I'm afraid we haven't been entirely honest with you,
  Bart. You see... you have a brother. Lisa:...
• Hibbert: But what to do with poor Hugo? Too crazy for Boys Town,
  too much of a boy for Crazy Town. The child...
• These candidates make me wanna vomit in terror! -
  Homer speaks out loud what we think, "Treehouse...
• Well, let's get started: you want to be on the right or the left?
  Hugo, about to sew himself to Bart, "Treehouse...
• Hibbert shows Bart-Hugo to Marge] [one of them starts gnawing the other ferociously] Marge:
  I think I'll bottle-feed that one. -- "Treehouse...
• Marge: Yes, doctor. It's what we've always feared: it's loose.
  Hugo is loose. See you soon! -- Casual phonecalls...
• Hibbert: You know, isn't it interesting how the left -
  or sinister -- twin is invariably the evil...
• Hibbert: There, there, Hugo. I understand. All those years caged up in here,
  why, you've probably never ever seen your own face...