Penny: (after Sheldon cited from Leonard and their roommate-agreement) You actually put that in an agreement?
Leonard: Yeah, we also put in what happens if one of us wins a MacArthur Grant, or if one of us gets superpowers, or if one of us is bitten by a zombie.
Sheldon: He can't kill me, even if I turn.
Penny: Is there anything in there about what if one of you gets a girlfriend?
Sheldon: No, that seemed a little far-fetched.