Perfect in every sense, but most particularly the humour.
Wonderful back and forth sniding going on there, with a side dish of fall-off-the-sofa witty asides. Your Severus is a gem, in that pre-diamond, still carbon way, and surprisingly fits well with his canon depiction. But it is your word choice, coupled with a decided knack for their placement and comic timing, that places this fic at the top of its genre.
Most definitely the most enjoyable thing to have passed my eyes in a long time ... my porn collection withstanding.