Sen Kagemiya

Sen Kagemiya (影宮閃, Kagemiya Sen) is an Ayakashi Majiri and a member of the Night Troop. He was formerly on a combat team with Gen Shishio, but disliked him because Gen's solitary nature made him difficult to understand and work with.

Appearance
Sen has blond hair and sharp eyes similar to Gen's. Both his hairstyle and face have an overall feminine look, which confuses more than a few people. His usual outfit consists his hair tied into a ponytail, green pants with blue suspenders, a tucked in black long sleeve shirt, and black fingerless gloves.

Personality
Sen has a very abrasive personality, and tends to snap at even his closest friends. He is especially critical of Gen and Yoshimori, though this seems to be because he envies their inner and outer strength, and wishes he was a better friend to them both. Sen is very afraid of bugs, and hates being told he resembles a girl more than anything else. He has a habit of stabbing Yoshimori in the head with a single claw when annoyed with him. Though Sen has trouble admitting when he is fond of someone, he is especially close to Kei Sazanami, who helps Sen master his mind reading technique. Oddly enough, Sen develops some habits and mannerisms that make him something of a replacement for Gen, such as joining Yoshimori in skipping class on the school roof.

History
Sen was one of several Night Troop members that had problems with Gen in the past. He resented Gen for charging into battle without working with comrades, and more than that, for defending Sen without being asked. When Sen approached Gen about the problems he was causing, Gen simply explained that he was doing the job that had been entrusted to him, but this did not make much sense to Sen.

Remembering Gen
In the manga, Sen attends Gen's funeral with the rest of the Night Troop (he skips the funeral in the anime, prompting a flashback of Shoki), but at first does not seem to care much. When Shu Akitsu assumes that Sen liked Gen, Sen becomes very defensive and embarrassed, and starts listing all of Gen's faults (which is usually a sign that Sen actually does like the person in question).

The Night Troop temporarily moves to Karasumori to help defend against Kokuboro, and Sen is unimpressed with Yoshimori as a Legitimate Successor. He challenges Yoshimori to a capture game (very much like the one Atora challenged the Kekkaishi and Gen with, except that this time, Yoshimori is alone against Sen, Shu, and Dai). Yoshimori manages to catch Dai, but is startled by the appearance of Shu's wings, allowing Sen to sneak up behind him and grab him by the throat. Sen assumes he has won and insults Yoshimori's abilities, but leaps away as Yoshimori activates his low-level Zekkai, destroying Sen's claws. Sen is puzzled and frustrated by Yoshimori's promise to avenge Gen's death.

Kokuboro's Hostages
Sen, Shu, and Dai watch the battle between Kokuboro's army and Karasumori's defenders from the sidelines. Sen sees Yoshimori and realizes he is searching for something, but can't tell what. Suddenly, Yoshimori abandons the battle. Tokine tries to stop him, but he tells her not to follow him. Tokine follows despite this, and so does Sen, even more curious about Yoshimori's plans.

Madarao leads Yoshimori to an Ayakashi in the human skin disguise, but it turns out to be Shion instead of Kaguro. Shion admits she wore it to draw out the Kekkaishi. Her spider goons attack Yoshimori, but he stops them easily. Shion explains she has been ordered to capture a Kekkaishi, and seeing this as his chance to find Kaguro, Yoshimori agrees to become her prisoner. Madarao tries to stop this, so Shion knocks him away. Shion binds Yoshimori with webbing, then does the same to Sen when she senses him watching. Shion recalls that Byaku actually ordered her to catch two Kekkaishi, and decides to try and pass Sen off as the second. Shion transports both Yoshimori and Sen to Kokuboro's dimension.

A bound Sen is brought into a room where Yoshimori is similarly bound. As a reminder that Yoshimori is a hostage and that they are in control, Byaku has two Ayakashi threaten to behead Sen. Byaku orders Yoshimori to submit to his control worm, reminding him that Sen could die in front of him, just like Gen did. Yoshimori appears to be ready to submit, but then unleashes a light aura that destroys his bindings and the worm. Shion quickly binds him again, so Yoshimori produces the dark aura again, which appears to destabilize the air around him. Hekian warns Byaku that Yoshimori may damage the castle further at this rate.

Sen is placed in a dungeon, and finds that his claws can't cut Shion's webbing. He wishes he hadn't worried about Yoshimori. Sen wonders if he will die, and recalls that Gen was able to be fearless because he was always prepared to die. Ashamed of himself for giving up so easily, Sen renews his struggle to break free, and Yoshimori bursts into the cell moments later. As Yoshimori sets him free, Sen begins to see several aspects of Gen in Yoshimori, which bothers him.

Tracking Kaguro
Sen follows Yoshimori away from the dungeon, amazed that he is able to handle so many Ayakashi so easily. Yoshimori mentions that there are worse ones in a room ahead, but so long as go through quietly, there shouldn't be any trouble. Suddenly, an enormous amount of Ayakashi bugs rush toward them, startling the pair.

Yoshimori protects himself and Sen with a Kekkai, but the Ayakashi ignore them and focus only on escaping. Sen is unable to remain calm around so many bugs, so Yoshimori raises his Kekkai to the next floor. Yoshimori teases Sen about being afraid of bugs, and Sen angrily asks why Yoshimori saved him if he is such a burden. Yoshimori says it's normal to save a friend, but this only irritates Sen, as it reminds him that Gen Shishio would save him without being asked as well. Yoshimori replies that he doesn't mind himself getting hurt, but that he can't allow others to be hurt around him. After they reach the outer part of the castle, Yoshimori tells Sen to follow the fleeing Ayakashi bugs and escape. Sen refuses, not wanting to get close to them, but Yoshimori makes a path through the air with his Kekkai, leaving Sen unable to follow him.

Sen manages to follow Yoshimori with some difficulty, and offers to find Kaguro for him. Sen explains that he can track powerful Ayakashi by their auras, but doing so leaves him vulnerable, so he asks Yoshimori to protect him. Sen flares his own aura, and detects several powerful Ayakashi. As Yoshimori begins to describe Kaguro, he suddenly remembers that Kaguro was wearing a human skin disguise, and assumes Sen won't be able to find him. Sen gets angry because he thought he would finally be able to help. Yoshimori apologizes and tells Sen to go home, and heads out to find Kaguro alone. Soon after, Tokine runs into Sen (literally), and he offers to track Yoshimori for her. Just as they find him, however, the building collapses around them. Sen manages to grab a broken post, but Tokine falls into a dark pit. Tokine later spots Yoshimori fighting Kaguro and is about to call out to him, but Sen grabs her, explaining that Yoshimori won't fight as well if he's distracted by her.

Suddenly, the castle begins to collapse around Yoshimori and Kaguro, and in the confusion, Yoshimori is grabbed by Sen. Yoshimori is surprised to find himself in a Kekkai with Sen and Tokine. They're both angry at him for not having a plan to defeat Kaguro, and tell him that just charging in won't work against Kaguro's power. Tokine uses broken blades from Kaguro's sword to show that the sharper the blades become, the more easily they pierce through Kekkai. Sen adds that Kaguro's last attack was so strong, Yoshimori's Zekkai didn't break the sword at all. Yoshimori says he knows all that already, but Sen insists that he's in over his head, since he can't even use Zekkai properly. Sen explains that he saw Masamori's Zekkai once, and it destroyed any part of the enemy that it touched. Yoshimori finally says he can't give up because Gen would laugh at him. Kaguro's next slash slices off the top of the building the trio are hiding in, even from a distance. Yoshimori pushes Tokine toward Sen, apologizes, and goes to fight Kaguro again.

Kaguro charges with his strongest attack yet, and Yoshimori braces himself with his Zekkai armor. Suddenly, Sen dives between them, attempting to use a broken piece of Kaguro's sword to block the hit. As Sen's blade piece begins to break under Kaguro's attack, Yoshimori instinctively activates Shinkai for the first time, bathing the area in a bright blue aura. The shockwaves from the Shinkai even reach Masamori's search party, causing them to worry and increase their speed. Kaguro is stunned to realize he's going to lose, and wonders why. Shortly after his sword breaks through Sen's, Kaguro's body is vaporized. Sen is completely shocked, unable to figure out what happened. He notices that Yoshimori isn't moving, and wonders if what he's seeing is a Zekkai.

As Masamori's search party nears the portal exit, Hakota spots Yoshimori, Sen, and Tokine with his enhanced vision. They finally enter the dimension, and are able to see Yoshimori's Shinkai from a great distance. Tokine calls to them, and Mukade sends one of his shadow bugs to pick her up. Masamori calls out to Sen, who tells him that something's wrong with Yoshimori: he isn't responding or even breathing. Masamori tries to force the Shinkai apart with his Zekkai, and tells Sen to hit Yoshimori, in hopes that he'll wake up. Tokine knows that Yoshimori wouldn't hesitate if he were in her place. She decides to use her phasing ability on the Shinkai and dives toward it. Tokine penetrates the Shinkai and grabs Yoshimori's hand, causing the Shinkai to fall with the help of a blast from Masamori's Zekkai. With Yoshimori and Sen saved, the group realizes that Kokuboro is crumbling away and makes their escape.

The Box Plot
Night Troup trainee Misao vanishes into a mysterious black box at Night Troop Headquarters. After the Amaarashi that emerges from the box is dealt with, Sen, Shu, and Dai alert Masamori to the presence of additional boxes.

The Intelligence Unit
After Kei Sazanami, Head of the Intelligence Unit, returns to Night Troop Headquarters, he decides to check the progress of Sen's training in mind-reading. Kei tells Sen to work on developing a better poker face, and warns Sen to be careful when training around the rest of the Night Troop, as he might give away his true intentions. However, he is satisfied that each of them has convincing camouflage: Sen is a receptive person with sharp senses, and Kei is talented at hypnosis and brainwashing. Kei is confident that no one suspects that they can both actually read what lies in the depths of people's minds. Sen admits that he has practiced reading the minds of random strangers, but he could only read surface thoughts that would be easily guessed simply by looking at their faces, and that anything he picked up would still be in jumbled bits and pieces. Kei stresses that this is why he must practice: to be able to screen out unimportant information and obtain the important information. He adds that they also can't read everything, so it is important to be able to fill in the rest with their own deductive skills.

Kei tells Sen to keep practicing, but warns him not to do so around Masamori, because Kekkaishi are very attuned to anything odd happening around them. He admits that other than fellow mind readers, Masamori is the only person that has been able to truly sense his abilities. Kei tells Sen that no one trusts a person who can read their hearts, and that alone, people like them are nothing. This makes Sen wonder why Kei leaked information on the Night Troop to enemies, and worries that Masamori has called Kei back to settle the matter. Kei admits this is correct, but isn't worried because he has made several outside contacts. He says Masamori is too young and soft to deal with him properly. Sen is alarmed when he realizes that Kei is planning to leave the Night Troop, and Kei invites him to come along, since it will give Sen more chances to improve his powers. Kei admits that while his position in the Night Troop is comfortable, he can't stand working under a man he can't read at all. Sen seriously considers Kei's offer, and wonders if it will really allow him to improve. However, Sen changes his mind after Kei abruptly did the same and is forced to stay with the Night Troop.

Sen and Shu transfer to the Intelligence Unit, and are ordered to investigate Karasumori. Sen's actual mission from Masamori is different from Shu's: he is investigating the Legitimate Successors chosen by Karasumori. Masamori shares his research on Karasumori's Legitimate Successors with Sen. Legitimate Successors rarely ever die while at Karasumori, and that even among them, there is in inequality of power: Tokiko was the strongest in her generation, and Yoshimori appears to be the strongest in his. Masamori asks Sen to study the conditions for becoming a Legitimate Successor, and any changes in them that may overlap with changes in Karasumori. Sen guesses that this is only the first part of what Masamori wants him to do.

Sen and Shu become students at Karasumori Academy for the new school year. Sen is in Yoshimori's class, but skips the first day. Sen becomes very popular at school, but Hiromu Tabata is unsuccessful in gathering any important data on him. Yoshimori later finds Sen on the roof, and comments on how sociable Sen has been. Sen admits its an act to help him fit in, and that he isn't here to have fun. Sen leaves feeling frustrated, annoyed that Yoshimori doesn't seem suspicious of him. Sen is then approached by two girls from his class. He recalls his lessons with Kei Sazanami, who advised him to only use mind-reading on normal people, and then only briefly, since his power tends to show in his eyes. He also suggested using conversation to help bring key thoughts to the forefront, making them easier to read. Sen asks the girls about Yoshimori, and they begin to discuss him.

That night, Yoshimori and Tokine pursue an Ayakashi at Karasumori, while Sen and Shu observe from a rooftop. Sen tells Shu to take over, and leaves to call Kei. Sen describes what an irritating target Yoshimori is to follow around, and that he doesn't feel motivated to complete the job. Kei advises him not to give up so soon, and to get rid of his guilty conscience so he can complete the job. Sen agrees to try, and asks that Sazanami continues to guide him.

The Butterfly Incident
While at school with Sen, Yoshimori senses a weak Ayakashi. He sends a Shikigami bird to investigate. Shu calls in to inform them that he just destroyed an Ayakashi. Assuming the matter is handled, Sen and Yoshimori are surprised when the Shikigami bird returns with a pair of butterfly Ayakashi. More butterflies begin to appear, so Yoshimori sends his Shikigami bird to deal with the ones outside, while he and Sen destroy the ones within the middle school. This continues until Shigemori arrives at the school. Intrigued by the idea that he might get to see all four Legitimate Successors in action at once, Sen suggests they need all the help they can get. At Yoshimori's request, Sen attempts to track the lead butterfly, but this fails because they are all exactly the same. He guesses they are reproducing by dividing. Sen gets a troublng call from Shu that the butterflies are beginning to have a negative impact on some people, and Sen realizes they are evolving. Yoshimori creates a desperate plan to surround the whole school with a Kekkai that only destroys the butterflies, but Tokiko Yukimura arrives to stop him since he lacks the proper skill needed. Tokiko plans to carry it out herself, but Shigemori objects because she might lose control of her power. Instead, he suggests that all four Kekkaishi form the Kekkai, which Tokine seconds. Tokiko eventually and reluctantly agrees. Sen calls Shu outside to observe with him as the Kekkai is formed. Though successful, while removing the butterflies from the school, the Kekkai becomes unstable. Tokiko manages to stabilize it, and through joint effort, the four Kekkaishi compress and destroy the Kekkai, and the butterflies as well. Sen notes that Tokiko was forced to handle things in such a rushed, risky way because of Yoshimori, whose power seems limitless while in Karasumori.

Sen later secretly follows Saki, the shrine maiden responsible for summoning the butterflies, and peers into her mind with his power. He is shocked by her prophetic vision of Karasumori's destruction. He shares this with Kei Sazanami, who advises him against sharing it, both because Sen is not supposed to read the minds of ability users, and because people behave differently when they hear a prophecy that involves them.

Powers & Abilities
Anti-Detection Skills: Sen apparently has some practice in masking his presence, though more powerful Ayakashi tend to sense him right away.

Mind Reading: Sen can read minds without transforming, though he is still perfecting this technique. His eyes still tend to change when using this power, as if he were entering his Ayakashi transformation.

Ayakashi Transformation: Cat: As an Ayakashi Majiri, Sen has access to a feline transformation. Though he has never been shown to have a full transformation, Sen still uses various partial transformations.
 * Claws: Sen is frequently seen growing long, dark claws when threatened. Oddly enough, he does this most often when attacking friends that annoy him.
 * Scent/Yōki Tracking: Sen's specialty is tracking Ayakashi (by scent in the anime, by yōki in the manga). To do this, he must access a transformation that, while not a full one, still encompasses his entire body. In this state, he is enveloped by an aura, and his eyes both widen and darken in color, taking on a feline appearance. At this point, Sen can approximate an Ayakashi's location, strength, abilities, and thoughts. When in great condition, he can also track humans. However, he must focus all of his senses while doing this, which leaves him defenseless, and any distractions can interrupt his concentration. While under Karasumori's influence, he also develops whisker marks on his face and sharpened teeth, in addition to his usual claws.

Trivia

 * Sen has a habit of commenting on what he sees as a person's defining characteristics, which is usually insulting. More than once he refers to Tokine as "Miss Short Skirt," and states, to her face, that she is "the type of girl who goes out of her way to crush men's hopes."