MARK LEYNER is the author of My Cousin, My Gastroenterologist; Et Tu, Babe; and The Tetherballs of Bougainville. He has written a variety of movies and television shows.

BILLY GOLDBERG, M.D., is an emergency medicine physician at Bellevue Hospital and NYU Langone Medical Center in New York City. He is also the host of a weekly show on Sirius Satellite Radio’s Doctor Radio channel.

Together, they are the authors of the #1 New York Times bestsellers Why Do Men Have Nipples? and Why Do Men Fall Asleep After Having Sex?