Whilst its name is unknown, this monster kakashi is one of the most powerful and dangerous of all the kakashi shown so far. It resembles a tailless lizard, with four legs and a head that doubles as a mouth. From here, a large laser can be shot. Whilst this, coupled with the ability to sprout tentacles made of energy, is dangerous, its most powerful weapon would be that it is able to devour the minds of humans. Because of this, it requires no Seki to control it. In that sense, it acts almost like a wild animal. Also, underneath its back, it has a secret hidden scythe, not unlike that of Kurumitsuha.
This monster kakashi was found (in its petrified form) by Kyohei, Aki and Mahiru, eight years before the storyline of the anime. Both Kyohei and Aki were able to sense a faint presence from it, meaning that if it had a Seki, it could be controlled. However, when the kakashi senses dark emotions from Aki, it awakens, breaking out of the shell that was covering it.
The kakashi monster attacking the Seki
The kakashi attacking Aki and devouring his emotions
Attacking the trio, it follows them out of the cave and into a clearing, where it continues to assault them. Despite Kurumitsiha, Magatsuhi and Kukiri all attacking it at the same time, it gets away almost unscathed. It continues to attack them, overwhelming Magatsuhi's barrier and breaking off one of Kurumitsuha's scythes. When Kurumitsuha managed to get underneath and attack, it reveals a hidden scythe appendage, piercing through Kurumitsuha before attempting to fire a laser at it. However, before this occurs, Kyohei and Kukiri attack from the sky, causing an explosion. When the smoke clears, it is revealed that Kukuri has lost an arm, and the kakashi is unharmed. It continues to fire lasers at the trio, even when they try to limp away, causing Kyohei's mind to "break" and open Kukiri's left arm. It is later revealed that Kyohei caused Kukiri's left arm to activate, opening and absorbing the laser shot by the monster kakashi. Kukiri then amplified and fired the laser back at the monster kakashi, completely destroying it. At the end of episode 13 of the anime, "Kuga Kyohei, the Seki" Aki tells Kyohei that the head of the Hyuga clan has the monsterous kakashi that attacked them. In another episode, the head of the Hyuga clan tells his aid that the reason that they were interested in Kirio and Utao was because he believed that their abilities would allow one of them to control Amaterasu. In the end of Episode 13 of the anime, it shows the Hyuga waking Amaterasu which now has the form of Kyohei and Kukuri. One can watch the final episode of Kamisama Dolls at this website and add what they think:http://www.animeseason.com/kamisama-dolls-episode-13/.