Unknown | Draco Malfoy

With the castle asleep, the entirety of the names on the map were very sedentary, and it wasn't until Harry had moved his wand closer to the map, about to mutter mischief managed, that he noticed movement.
The movement was curious for a number of reasons, causing Harry to stare intently at the spot on the map. For one thing, the movement was not yet in the castle, but walking quickly along the very passage that Harry had taken in his third year to get to Hogsmeade. For another thing, the movement, the object, the person, was curiously named: unknown.

( hp half-blood prince - deathly hallows )
( previously entitled the girl with the book )