Messenger from the Urakai Kekkaishi : Season 1 Episode 22

Yoshimori and Tokine find out that the transfer student, Gen Shishio, is a member of Masamori's Night Troop and was in fact sent by Masamori to protect the Kekkaishi of Karasumori. Meanwhile gramps is doing some research on the "skin" that the Ayakashi dropped.