Dr. Lorvis: Can I ask you a question? You're a guy like me, how'd you get a girl like Penny?
Leonard: Well, just being myself really.
Sheldon: Oh please. I'll tell you how he did it. Implacable relentless badgering. In urology terms, he was a drug-resistant staph infection and she was a urethra that could not shake him.
Leonard: I don't know that I'd call myself an infection.
Howard: A gallant man would defend his fiance for being called a urethra.