Certain Magical Index, Vol. 19 (manga)

To quash an attack by God's Right Seat on Academy City, the mysterious Aleister Crowley will utilize even the corrupted power of an angel. But when Touma discovers that angel's identity, he'll stop at nothing to save her. Meanwhile, Accelerator is on a mission of his own to rescue Last Order from the ruthless Kihara. Could these seemingly unrelated battles actually be two sides of the same coin...?!