I understand why people kill.

I would too.

I can't stand seeing happy people. I want to shoot them dead.
I can't stand people who squeal and laugh like a chipmunk. I want to strangle them.
I can't stand people a certain person who acts like you're way below her level. I'm so fed up with her I want to chop her up.

If I do end up killing one of those three people, these are my reasons.

They're all fake assholes and conformists. People with no backbone.
Can't stand these type of people the most.