Wow, that is, indeed, quite filthy. But it's not the steaming hot sex that makes it brilliant, it's the feelings. It's Ginny's knowledge that she needs this, and doesn't want it, but wants it. It's the fact that Blaise is so obviously head over heels for her, enough so that he'll keep giving her this, keep trying to beg even though he knows nothing is going to change. Wonderful. Definite kudos.