6. Major Frank Burns and Major Margaret "Hot Lips" Houlihan on M*A*S*H
Played by: Larry Linville and Loretta Switt
Though she's a disciplinarian of a head nurse, Margaret Houlihan is a devil in the sack, having picked up the name "Hot Lips" when a sexual encounter between her and Frank was accidentally broadcast over the camp's PA system. Major Burns, by the way, is married, making the most significant romantic relationship on the show an extramarital affair—nice.