The Mystery of Karasumori.Hekian, a cloaked ayakashi plans to draw out the former deity of the Karasumori site, who is Lord Uro, by using his thousand eyes ability. Sakon summons the ayakashi called Field Guardian to absorb the waters of a swamp, that being the Colorless Marsh. The next morning, Yoshimori and Tokine go to the dry marsh to find Lord Uro, only to be met by Mamezo, who confirms that the Kokuboro was to blame for the marsh being empty. Shigemori is aware that the Kokuburo is researching about the mysteries of Karasumori. At night, Yoshimori and Tokine come across Hekian, who uses a binding shadow attack to immobilize them. Even though he is unable to use his thousand eyes ability at the school grounds, he is able to evaluate the barrier techniques and the legitimate heirs of the kekkaishi, to which Byaku informs Princess of this.