Friend: If you don't like my bad jokes, I will tell some stand up comedy.
Me: But you are not standing:)
Listen up, buttercup. The friend says he'll do "stand up" comedy, which usually means the comedian is literally standing up while telling jokes. But the joke teller points out that the friend isn't standing up. It's called situational irony because the friend's statement implies a physical action (standing) that isn't actually happening. You probably have the same problem, I bet you say you are gonna do things but never do them.