Yo Mama Needs Yo Papa

Listen up, buttercup. The joke is that "yo mama" is so obese that a regular scale won't do the trick. They gotta use her husband, "yo papa," as a counterweight on some super-sized scale. It's funny because it's ridiculously insulting. BTW, you look like you have never seen the sun, which means you are vitamin D deficient. Go outside sometimes, for god's sake.