Re: 15th
It was obvious when the conversation veered down too miserable of a path; Derek was still holding Stiles' cock out of the way and it was noticeable as it began to soften. The goal here wasn't coming - not for either of them, really - so Derek wasn't too bothered, but he did brace his body ever so slightly in case Stiles thought it was time to try fighting back again.
"I like your skin," Derek muttered as way of explanation. "I want to see more of it." And he wanted to put his mouth against all the newly exposed areas - wanted to taste them to see if they were as delectable as they looked. With all the hair above Stiles' cock perfectly removed, Derek continued to hold up Stiles' cock as he moved lower. He was silent as he worked, methodical, careful with his words.
"There'll be a punishment at another time for attacking me today," he said in a quiet, even voice, "but you've been behaving well otherwise. Would you like something nice as a reward?" Even as he said this, he carefully started shaving Stiles' sac, using his thumb to keep the delicate skin taut, caressing Stiles' balls in the process.