Seven

Seven (セブン) is a recurring character in the Phase Shift novels, one of the Ten Sages, Yukianesa's first wielder, and a successor to the head of the Twelve Originators' Kisaragi household.

Appearance
Seven is a tall young man with a pale slender face, light blue eyes and long, blond, shoulder blade length hair. He wears a pair of sleek rimless glasses with a button up white trench coat with golden buttons, underneath this, he wears a pair of sensible white jeans and formal black shoes. His look is topped off with a blue scarf underneath his coat, the purple hat that all Ten Sages wear and a white and black cape with golden embroidery.

Personality
Unlike his associate Eight, Seven is cool, calm and focused – saying little unless needed. His calm demeanor helps lend strength to his words, allowing him to get what he desires. Compared to the other young Ten Sages, Seven is far more serious about his work and how to go about it.

History
A member of the Ten Sages who hails from Magic City Ishana's Kisaragi household; Seven is introduced in Phase Shift 2 alongside his fellow Sage; Eight. Both of the Sages desired to have the Arch-Enemy Event Weapon, Highlander: Takemikazuchi, finished after Nine dropped the project and ordered it to be disposed of, however, neither of the Sages had the necessary power to finish the project as only the power held by Celica Ayatsuki Mercury would be able to complete the Arch-Enemy. When discussing on how to proceed, they were eavesdropped by Kazuma Kval who chimed in; introducing himself as Yūki Terumi. Both Seven and Eight are well aware of the man's existence and the three conspire on a plan to have the Arch-Enemy finished at last.

Finding Celica alone, Seven converses with her in an attempt to persuade her to help finish the project and further his research; but she denies on the grounds that Nine has already wished against it and promptly leaves Seven to his frustration. Knowing that there is no way that Celica would willingly cooperate with the project; Seven, Eight and Kazuma agree on trying to force her to help them by using the return of the Black Beast as a fear fueled motive to help; after gathering the data on her from her helping them, they would use the said data to create a control system that would effectively replace the need for Celica's power and presence.

Sometime later, the Black Beast rose again after its year in hibernation. Seven and Eight summon Takemikazuchi near Celica and use it to drain her magical power, however, this was stopped short by Celica's Arch-Enemy; the Machine God: Nirvana, who successfully attacked it's fellow Arch-Enemy and prevented it's wielder's demise, but it was unable to stop her from falling into a short term coma. With its new founded, although limited, power, Takemikazuchi fired upon the Black Beast; however, it's severe lack of power meant that the shot was unable to kill the Black Beast, instead, it only forced it into an immediate retreat.

Annoyed that Takemikazuchi was now dormant once more, Eight and Seven begin a manhunt in Magic City Ishana for Celica, Nine and the Six Heroes, in the hopes that they can use them to fuel and control the giant Arch-Enemy. However, the entire hunt was foiled by Suzukaka and Totokaka, who aided the group in their escape from the magic capital and then guided them to the Kaka Village. At their last straw, Seven and Eight finally decided that they can do without the Heroes and Celica and instead do the one thing that they had hoped against; use the traditional smelting methods of an Arch-Enemy by sacrificing a multitude of souls; however, the smelting method of finishing the Arch-Enemies had a drawback: it's incredibly difficult to control the Arch-Enemies afterwards. By the time that the smelting had finished, the Six Heroes had arrived too late to stop it and the Arch-Enemies consumed the lives of thousands.

Seeing that Takemikazuchi had been finished, the Black Beast teleported behind the Arch-Enemy and began ripping it to pieces. Scared of losing the project that they had been working so hard on, Seven and Eight teleported the Arch-Enemy back to Magic City Ishana, however, the teleport failed to go as planned as one of the heads of the Black Beast was stuck on the Arch-Enemy. Instead of teleporting to the designated site where Seven and Eight were waiting, the satellite Arch-Enemy crashed into Magic City Ishana's buildings, killing thousands of innocents. The catastrophe did not end there, the subsequent result of one of the heads (which was still alive and mentally connected to its body) being teleported to Magic City Ishana meant that the Black Beast was now fully aware of where Magic City Ishana lay in the world, and as a consequence, began its journey towards the capital.

An unspecified time after the war, Seven succeeded to the head of the Kisaragi house. In an 'attempt' to hide away his Arch-Enemy, the Ice Sword: Yukianesa, he invited Eight to the Kisaragi household and asked her to take and hide it. When Eight touched the Arch-Enemy, everything in the room became instantly coated in a thick layer of ice, save Yukianesa and Seven, and Eight lost her life. Happy with the outcome of his plot to kill Eight, he promptly hid her corpse and Yukianesa, making up a cover-up story about Eight stealing the Yukianesa to never be seen or heard from again.

Powers and abilities
As one of the Ten Sages, Seven possessed incredibly powerful magical skills, enough to be even able to face off against the great witch Nine. In addition to this, he wielded Yukianesa, and was shown to be able to use it with incredible skill.

Trivia

 * Seven is never talked about after the Phase Shift novels and thus, his fate is left unknown.
 * Given that he is/was the head of the Kisaragi household, it's reasonable to assume that his last name is Kisaragi.