Um, professor umbridge from Harry Potter. She's basically an asshole just to be one.
The other ones all have some sort of justification to their shittyness. Jenny was abused, Vader was a literal slave that was taken advantage of by both the Jedi and palpatine. The joker has literal mental issues.
Umbridge was straight up a child abuser with no remorse or tragic back story. She harmed kids while enjoying it and drinking tea.
You do know that thin film clear "plastic" isn't actually plastic right? Most of that is cellophane, which is made from plants and is biodegradable.