Lack of Respect
Telling your friends they're a waste of oxygen when they've helped you through every single mess.
My friend helped me with my homework and I told him he was a waste of air. I got an F. He got a B. I’m a waste of time.
She helped me with my dog and I called her a waste of breath. My dog ate her shoe. She got a new one.
He helped me during the fire drill and I said he was a waste of space. I got out first. He got a burn.