The Dreaming manga volume 2

Identical twins Jeanie and Amber arrive at their new boarding school on the edge of the Australian bush to find it steeped in mystery. Vague rumors of students disappearing, sealed rooms, tight-lipped teachers, and a collection of disturbing paintings have the girls unnerved, and when they start experiencing the same nightmare, they really begin to worry. The subtle buildup of spooky tension culminates when one of the girls' friends goes missing, only to turn up dead.