Now you know what pet peeves are!
A pet peeve has nothing to do with a dog, cat or any sort of pet. A pet peeve (noun) actually means an experience or behavior that really bothers and irritates you (and you probably complain about). You will find that a lot of these pet peeves involve manners, family, relationships, and hygiene.
We all have different pet peeves and some particular behavior may be more irritating to you than someone else. I think one of my biggest pet peeves is when people don't say "thank you" when you hold the door for them. That really irritates me because it doesn't take a lot of effort to say two words! What is one behavior that really bothers and irritates you?