Why did the hedgehog cross the road?
To check in on his flat mate.
Hedgehog Crosses the Road
Explanation
Explain Bear
Listen here, buttercup. The joke is a pun! Hedgehogs are flat, get it? Just like your brain after trying to understand this joke, HA! It's also a play on the phrase "check in on his flat mate". Now go back to watching your cartoons.