The kind of person that bans yours or another teammates champ in pre-game lobby when you have it hovered. Then when you ask why, they don't respond. If I ban someones champ on a non ranked match, I'll say "sorry I'll dodge" And then I dodge. If I ban it in ranked, I'll still say sorry.
Edit: I think you guys are projecting. I don't get tilted when someone bans my champ. I get annoyed. Who wouldn't? No people tend to go "Ok I'm going to feed now". That's happened, and I don't want that in ranked.