Sam continued to stroke Dean through his orgasm before letting go of Dean's cock to wrap both arms tight around his waist as he continued to thrust hard. He'd apparently lost all ability to form coherent sentences.
He bit down on Dean's shoulder, even drawing blood from him - sorry Dean. He continued to lap and kiss and suck at that one bloodied mark as he thrust. It didn't take many more thrusts before he was burying himself deep inside Dean, growling out his name as he came inside.