2013-09-20
Explanation
This comic depicts a man waking up screaming in bed next to his partner. He says "AAAAH!" and she asks "What?!" He describes his nightmare: he had a dream where his parents were zombies, and they came to his house and were eating his flesh, and other horrifying events unfolded. He goes on to describe further disturbing elements of the dream, concluding with details that make the nightmare sound truly terrifying.
His partner listens and then makes a pointed observation, noticing that despite the horrifying content of his dream, he apparently woke up with an erection. He defensively exclaims: "That'''s biological!" The joke plays on the well-known physiological phenomenon of nocturnal erections (sometimes called "morning wood"), which occur during REM sleep regardless of dream content. The man is embarrassed because his body'''s automatic response seems to contradict the terrifying nature of his nightmare, and he has to awkwardly explain that it has nothing to do with the content of the dream.
The votey shows the man peacefully sleeping, perhaps suggesting he has drifted back to sleep despite the awkward conversation, or implying the whole exchange might itself have been a dream.