VERY hot! I love the hints of defiance with Narcissa and how she's not completely submissive. I also like how both she and Severus aren't unwilling. It's that hint of desire you've portrayed between them that makes this so hot. Of course the bondage is also hot and the slight transfiguration, too, but the combination of all three and not focusing too much on one thing or another is what really makes this. Great job, mystery author! :D