The Eminence in Shadow, Vol. 3 (light novel)  (English, Hardcover, Aizawa Daisuke)

An invitation to an unfamiliar city can only mean something fun is about to go down. Sid follows Claire to the lawless city, where he's launched into his newest quest: to hunt down the founding vampire, the Queen of Blood, sleeping somewhere in this land. On the journey, he crosses paths with a mysterious girl-Mary, known as the oldest vampire hunter. Things are about to get messy between the most powerful players in the lawless city and the Shadow Garden, as they get one step closer to uncovering crucial information about the Possessed.