Puck may not be the smartest guy in the school, but he was certainly smarter than Finn, and it really was just wishful thinking on his part to believe that he'd actually been invited to a swingers party. He'd be damned though if he was going to spend his whole summer with Rachel Berry as his soundtrack to summer-besides she hadn't even let him touch her boobs when they were "dating".
"Ok hold up. Who says we're all on board with this plan? I don't want to spend my whole summer with you guys-especially Rachel. I have plans."