I get that they're criminals, but I still say that their greatest crime isn't poke-theft. It's devoting their lives to STALKING CHILDREN!
To a child's eyes, Helga is the hopeless victim of unrequited love. To an adult's eyes, Helga is really just a child with rage issues who has turned to stalking her classmate in order to cope with her horrible home life.
Given that their main goal is trying to destroy three little girls, all Powerpuff Girls villains are pretty messed up. Still, in the contest of whose the most disturbing, Him is the hands down winner. This is because Him is no ordinary monster. No, he's pretty clearly Satan. (You know, if Satan spliced his DNA with a lobster and dressed like a drag version of Santa Clause.)
Momma had a chicken! Momma had a cow... wait what? I don't know how this woman is giving birth to livestock, but I am certain there is a really fucked up story there.
Given that the show he's in is basically just a serial killer's fever dream, Eustace may seem like an odd choice for most disturbing, but think about it: How many times in the series' run did Eustace emotionally and physically abuse Courage. He enjoys animal cruelty so much, in fact, that he owns a mask specifically for that purpose. It's no wonder Courage is so jittery all the time. He's basically one of those Sarah McLachlan dogs.
He's a little boy whose best friend is a piece of wood? Oh, that's kind of cute. Oh, no, wait. He's a little boy that everyone is annoyed by and whose parents are nowhere to be found, whose best friend is a piece of wood. Yeah, that's really, really depressing.
Mr. Crocker is an obviously insane elementary school teacher who is singularly obsessed with one of the students in his class. I think Timmy's next wish should be for more thorough background checks in our public schools.
In all their investigations into the paranormal, did Mystery Inc. never think to investigate why THEIR DOG IS FUCKING TALKING?!? Does nobody else find that terrifying?