Sheldon had gotten a research physicist from his uni to play as his cousin, Leopold, to further and solidify the lie to Penny. You were Penny's best friend who lived with her, knowing about the lie and more interested in Toby, or Leo, than the situation.

Eventually Leonard left with Penny, Sheldon going back to his room as Toby sighed. "I cannot work like this." He groaned softly, his hands on his hips.