Isaac's throat opened up easily for his Master's length, but that didn't stop the muscles from reflexively opening and closing, like the beating of a hummingbird's wings. For a moment he closed his eyes, taking it all in; the feeling of being full, controlled, and the heavy scent of Derek all around him.
Once he had found that content feeling, in the center of his chest, he opened his eyes, daring to look up into Derek's. His gaze was one that showed complete trust, and love.