The nails were what did it, really, arching in a slow undulation to press himself up into the slow, faintly stinging drag of Soren's fingers, feeling pleasure curling tighter in the pit of his stomach, threatening to unravel at any moment.
There was another low sound, keening faintly and giving Soren's hair another tug, just at the moment it was the best he could manage as far as warnings went.