Yes. I thought it was probably going to be Sirius.
I think I'm not going to write Snape Manor now. I'm stunned. The description of Sirius' house is so much like what I had in mind for Snape Manor. She had infestations, I had more magical objects. She had screaming portraits of old relatives, I had relatives appearing in reflections - but it's so close to Snape Manor, and the feel of it, that I was totally discouraged as I read those scenes.
On the other hand, the description of the Ministry is exactly what I needed for 'Beg Me For It.' Glad I haven't written 'SNAFU' yet.