Sheldon: (Knock * 3) Leonard?
Leonard: Shh. Just pretend we're not here.
Sheldon: (Knock * 3) Leonard?
Leonard: I'm sure he'll go away.
Sheldon: I'm just going to keep knocking till you answer. (Knock * 3) Leonard? (Knock * 3) Leonard? (Knock * 3) Leonard?
Leonard: What do you want? I didn't say come in!
Sheldon: You asked what I wanted. I wanted to come in. I'm here because you violated our roommate agreement. Specifically, section eight, visitors, subsection C, females, paragraph four, coitus. Roommates shall give each other 12 hours notice of impending coitus.
Leonard: I didn't even know her 12 hours ago.
Joyce Kim: That's it! I'm out of here!
Leonard: But, Joyce, come on.
Sheldon: 12 hours? [Looking judgmentally]