"It's really me," Peter confirmed. He didn't get offended, since Sylar thought he was an illusion at first, too. "And I'm not leaving you alone here. This is all just in your head, Elektra. But I can get you out."

He hadn't realized yet that this was just a trick of the castle. Maybe because his telepathy and empathy were working against him, but so far to him it really did seem like he was in Elektra's mind.