"I don't know how he could be either, with your cock halfway down his throat, Master," Isaac joked, taking a quick look at Stiles, before nuzzling along the line of Derek's jaw. The kiss had taken a good chunk out of his patience however, and he quickly moved back into place, curling his hand around Stiles' length, and giving him one solid stroke.
"Oh, he's hard enough, all right," he said softly, leaning down to run his teeth over the flesh of the slave's hip. He pooled a small amount of the lube in his palm, letting his body heat warm it, before he ran it over the length of Stiles cock. The metal had already warmed, and he carefully manoeuvred it into place, feeling sorry for the boy, for a fleeting moment. After all, Stiles would be fucking Isaac, and he wanted this to last a good long time.