A war-thirsty demon has forged a contract with a berserker. Its goal, to see the world caught up in an endless war, starting with demons invading the streets of London. As the number of cases involving demons grow, members of Sword Cross find themselves overwhelmed.

Wisteria soon hears that her brother Snow has been captured, and turns back to return to London, seeking to rescue him.

As new and old faces alike cross paths, what will become of their fates?