The Eminence in Shadow, Vol. 5 (light novel)

BEFORE MUCH LONGER... THE WHITE FOG WILL ENGULF THE WORLD IN SILENCEAll is well at the Midgar Academy for Dark Knights, but then something wicked suddenly draws near: The students are vanishing one by one-even Cid's older sister, Claire! Zeta of the Seven Shadows sets off to investigate, while Cid and Alexia embark for Claire's room where they find...an ancient script, cool magic circles, and incantations that seem important and yet don't actually do anything whatsoever. What does it all mean, and why has Claire been talking to herself so much lately...?