When suffering from a hangover, all areas of the human body seem to shut down - all functions are inoperable or at least you don't have the energy to try them. All that is, bar one. Despite feeling that you're close to death, the libido not only remains, but seems to be heightened - congratulations, you have the Hangover Horn.
Sarah: Jesus, where have you been, I've been phoning you for ages?!
Mike: Sorry, I was out drinking last night. I've got the Hangover Horn, you caught me on the up stroke.