The Invisible Girl of Blesswood Boarding School

Dark walls and creaky floorboards, the gaze of a strict matron, a cold attic hiding secrets. This is how Blesswood Boarding School welcomes new students on their first day. Inseparable twins Aura and Aiden do not yet know that dark... surprises await them here, which will soon change their lives…
 
Studying at the boarding school promises to be boring until the brother and sister meet Natasha - a girl who is invisible to everyone except them. But the ghostly stranger remembers almost nothing. Her last memory is a mysterious box found in the attic of Blesswood. Aura and Aiden decide to unravel Natasha's mystery and restore the events that led to her confinement in this strange place.
But time is short, for a dangerous monster watches her from the dark corners of the castle. Who is Natasha really? And why is she being pursued?