A whole host of people:
People who talk way too much / you cannot conversate with them
Self absorbed/ narcissistic / never ask you anything about your life, it is always only about theirs
Manipulative
Rude/ unnecessarily vulgar/inconsiderate
Unhygienic
Says really dumb things that they haven't really thought about
Forces their beliefs on me
People who aren't conscientious or care about responsibilities or consequences of their actions
People who don't care about absolutely anything
People who litter or endanger others
If a friendly kind hearted dog shows they dislike a person (it's usually for good reason)
If I get a bad vibe in general
If they turn a devastating public event around to get some sympathy, despite not being directly affected by said event/tragedy
It's no surprise why I am usually alone, haha! There's more I could add to that list too.