Assuming that anyone who has different opinion or belief is stupid. I don't get it why some people can't respect other people's opinions, whether it is their belief and views toward any matters. Close-mindedly thinking that their opinion is the truest and cannot be turned down. I think it is such a big turn-off.
People who try to make conversations when I am reading and/or listening music/whatever with earphones on. It really gets on my nerves. When someone assumes that when we are reading a book that we are "doing nothing" and therefore can be interrupted, repeatedly. Sometimes all I need is solitude and locked myself from the real life with my favorite books and drowns to a fantasy without worrying about anything else. It is my own way for self-loving, and I need that in life. Some other time, I just don't want to talk with anyone.
People who finds everything to complain about. Those who blame anything but themselves for their own failure. Well, I do complain about a lot of things too, but I am trying as hard to finish and deal with it as soon as I get my mood back. At least I tried.
People that simply cannot take their trash to the trash bin in places. Littering everywhere or throwing paper trash or whatever it is through your car window. Or throw their empty bottles or cans to everywhere they like (and inside pots) and never felt guilty of it.
Smoking in public area. I really cannot stand smoke, especially cigarettes. And people who do this in public, while they're driving, or talk. And their breath smells like cigarettes. Or they smoke in public and the smoke goes everywhere all over people's face and they keep suck it, though you realized that people around them are closing their nose and gazed at them. Even if their clothes smells like cigarettes. Seriously?
That's my top 5 pet peeves (I wish I could add more) and that's really...really annoying, not only for me but also other people. So, what are your pet peeves?