Certain Magical Index Light Novel Softcover Volume 18

"Index has returned to London, only to find herself in the center of a coup-d'etat! After the Knights seize the UK, the country is put under martial law while the sorcerers of the Puritan faction continue to resist. As the civil war rages, Touma Kamijou follows Index's trail to Folkestone where he runs directly into the mastermind of the coup herself, the second princess Carissa and God's Right Seat Acqua?!"