Doonesbury by Garry Trudeau for March 11, 1987
Sal: Dr. Whoopee's the name, safety my game! Girl: Won't you come in, doctor? Sal: Got your message on my service. what can I do you for? Girl: Arn? Arn: Do you give discounts on quantity, doc? Sal: What kind of quantity are we talking here, chief? Arn: Three gross. Sal: Boy! You guys are cautious! Girl: Arnie's a safe sex machine.