Sheldon: Oh, Leonard, I have something for you. Per our roommate agreement, this is your 24-hour notice that I will be having a non-related female spending two nights in our apartment.
Leonard: When you say non-related female, you still mean human, right?
Sheldon: Of course. Pets are banned under the roommate agreement, with the exception of service animals, such as seeing eye dogs and, one day, cybernetically enhanced helper monkeys.