Butt Cheeks' Journey

Alright, listen up, buttercup. This "joke" is playing on the fact that the word "they" can refer to a group of people that have been through a lot. But the punchline reveals that "they" actually refers to your butt cheeks, which have been through the krapping process of sitting all day. It's supposed to be funny because it's unexpected and slightly vulgar. You probably have hemorrhoids.