Very HOT. Especially (oh especially, especially) Snape's gloved hand on Harry's thigh. Snape's expression, Harry's position, socks! Love that Snape is dressed (sharp uniform!) and Harry's totally naked (except for socks!) And the magic going on in the background, and the painting, which is compelling all by itself, but which also adds a certain je ne sais quoi (and I know exactly what I mean.) Lovely.