Sam didn't need telling twice. He curled a hand around Dean's length stroking in time with his thrusts. The angle was awkward and unnatural and a little clumsy, but it didn't seem to matter. It offered the friction Dean so desperately craved.
He wasn't entirely sure how Dean was still able to string a sentence together when he was struggling with single words. Maybe he was going to fail his challenge after all. His arm wrapped tighter around Dean as he all but held him in place, thrusting harder into him. "Dean..." He kissed and bit just below Dean's ear, teeth scraping tender flesh. "I can't... I'm not gonna... much longer..."