I hate it when someone won't SHUT THE FUCK UP about something. Like I want to stay inside and eat and not move much becuase it's basically a completely indica strain, and they want to go outside at 2 in the morning to go on a walk. So I tell them they can go, but they wont unless I come. And I don't want to.
And then they spend the next two hours talking about going outside, pleading, and i'm a nice guy who's also high so I tolerate it every time and then finally my high starts wearing off and the annoying bitch won't fucking stop and the usually locked-away rage starts building and I end up either yelling or locking myself in another room with my bong to get away from this person.
I also hate jackasses who have no respect for your property, privacy, or order. They'll end up doing stupid shit like tearing little bits of paper up and spitting them all over you and your desk for fun, they'll throw up somewhere and not clean it up, or they'll just leave all their food plates/glasses wherever and forget about them...