"Of course you wouldn't," Draco sniffs. He's just assuming she's some minor Hogwarts ghost he's never met before, and few people at Hogwarts, dead or alive, seem to be all that familiar with Pigfarts. Only the highest caliber wizards are aware of the Martian institute, which is exactly as it should be. Not that it doesn't stop Draco from name-dropping the place to almost everyone he meets.

"Pigfarts is a much better school than Hogwarts, and Rumbleroar is the headmaster. He's a lion... that can talk." And, presumably, rough up any mischievous poltergeists such as this one. Draco raises his eyebrows at the ghost, waiting for her to be suitably impressed.