Jack-o-lard
That person who won't stop nagging you for something, but once they get it, they’re too full of themselves to even look at you.
He kept asking me for my snack. When I gave it to him, he just said 'Whatever' and walked away.
She kept begging me to let her borrow my pencil. When I said yes, she acted like I was doing her a huge favor.
He kept yelling at me about my mistake. When I fixed it, he just said 'Whatever' and left.