Blue Exorcist, Volume 21 (Blue Exorcist #94-98)

An attack on Tokyo by a huge demon that is visible to almost everyone marks the start of an unprecedented outbreak of demonic activity around the world. While the Knights of the True Cross and the Japanese government scramble to contain the damage, Lightning's investigation into the Illuminati has pushed the Knights of the True Cross - and Yukio - just a little too far. Now Yukio rushes to confront Mephisto, determined to hear the truth of the circumstances of his and Rin's birth. Yet Mephisto, aloof as always, still seems to be pulling everyone's strings. For Yukio and Rin, there will be no easy answers...