ข้อมูลอนิเมะBeyond the Boundary

While contemplating the act of suicide, second year high school student Akihito Kanbara notices the freshman, Mirai Kuriyama about to jump off of the school roof and instinctively goes to save her. Annoyed by his attempt to stop her, Mirai impales Akihito through the heart with a carmine sword. Some time later, Akihito and his friend Mitsuki Nase work on preparing an anthology for their Literary Club when Mirai disturbs them. It is revealed that Mirai had been stalking Akihito all week in an attempt to kill him. However Akihito outlines her futile attempts due to his immortality as a half-youmu. Afterwards, Mitsuki teases Akihito on being stalked by Mirai and advises him to steer clear of the latter. When confronted by Mirai after school once more, Akihito learns that that the Kuriyama clan was wiped out because of their powerful ability to create weapons from their own blood, leaving the former as the lone survivor. Afterwards, Mirai chases Akihito into a classroom when they are suddenly interrupted by a youmu crashing through the window, although famous Spirit World Warrior—Shizuku Ninomiya quickly deals with it. Akihito later treats Mirai to dinner and learns that she had been merely using him as battle practice before being left with an unanswered question. Meanwhile, Shizuku kills the previous youmu and extracts a crystal ore at its core. The next day, Mitsuki once again warns Akihito to avoid Mirai, but he instead chooses to talk with the latter after school. While having dinner at the playground, Akihito learns that a youmu had been haunting Mirai's home, in addition to her hate towards her cursed ability as well as the act of killing. Empathizing with her, Akihito decides to help Mirai kill the youmu and both confront it at her home.

Akihito momentarily spaces out as they face the youmu although Mirai manages to drive it outdoors. Mirai chases and engages the youmu into a ferocious battle at the playground and after a bit of a struggle, strikes near its eye albeit escaping. Loosing the resolve to follow through, Mirai suggests they leave it be, but ends up chasing after it following Akihito's warning of her declining living expenses. Mirai then removes her ring, amplifying her powers further and splashes acidic blood on the youmu. Now immobilized, Mirai destroys its eye—killing it in the process and revealing an ultramarine crystal at its core. Akihito then mends Mirai's wounds and offers to let her join the Literary Club, which she rejects before passing out. The next day, Akihito and Mirai take the youmu crystal to an appraiser but are instead greeted by the humanoid youmu—Ai Shindō, prompting Mirai to instinctively draw her sword before they explain the many natures of youmu and the appraising process to her. While at school, Akihito tries to gather information on the aggressiveness of the recent youmu attacks from Hiroomi Nase, to no avail. Afterwards, Akihito visits the appraiser—Ayaka Shindō to get her to reveal the contents of a postcard from his mother—Yayoi Kanbara, where she warns him of the coming of a youmu known as the "Hollow Shadow"—a powerful youmu lacking a physical body. Ayaka explains that following its last appearance, it easily defeated five A-level Spirit Warriors and the recent low-level youmu were probably agitated by its proximity. Afterwards, Ayaka appraises Mirai's youmu and she uses the money to treat Akihito to a beef bowl as thanks for his help. Mirai then pleads with Akihito to not get involved with her further, since she isn't allowed to live like he does because she had killed someone.

The following day Mirai chases a low-level youmu and after finding herself unable to kill it, Mitsuki appears and kills it, offering Mirai its crystal which she rejects as charity. Meanwhile, an interrogation officer from the Spirit World Warriors' Observation Department—Miroku Fujima meets with Izumi Nase to discuss the coming of the Hollow Shadow. While at school, Akihito tries once more in vain to get Mirai to visit the Literary Club and in obtaining information about the latter from Hiroomi. Mitsuki later has Akihito rendezvous with him at the train yard to disclose some sensitive information she obtained from Iori Ichinomiya. Mitsuki reveals that Mirai may go after the Hollow Shadow and of her adoption by the Inami clan who lost their daughter at the hands of Mirai while confronting the youmu itself. Meanwhile, as the Hollow Shadow enters Nagatsuki City and causes the moon to cast an eerie purple glow, Akihito tries to stop Mirai from going after it. Mirai tells Akihito of her connection to the Inami clan and that she murdered her friend—Yui Inami, out of fear after the Hollow Shadow possessed her. However despite Akihito's pleas that their lives aren't different, Mirai bars him from going with her. Afterwards Spirit World Warriors in the area are tasked with setting up barriers to guide the Hollow Shadow out of the city. As the youmu in the area become increasingly influenced with malice by the Hollow Shadow, Mirai makes her way to the city limits and prepares to confront it. However Sakura Inami attacks her with killing intent just as they both become engulfed and thrown into a random part of the city by the Hollow Shadow. Finally, Akihito suddenly stops Sakura's attack and states that Mirai still didn't understand his words.

Akihito and Mirai flee from Sakura'a onslaught down the illusory labyrinth created by the Hollow Shadow. Arriving at a twisted replication of the train yard, Mirai becomes ensnared by the Shadow as it mimics Yui's likeness, however Akihito snaps Mirai back to reality before the Shadow kills her. Revealing its main body, the Shadow attacks Mirai who retaliates by injecting its body with a massive amount of corrosive blood which destroys it. Finding themselves back on the mountaintop, Mirai questions her self image to Akihito. As Akihito sincerely replies, the weakened Shadow suddenly possesses his body, causing him to plead with a horrified Mirai to inject him with her blood. This forces the Shadow out of Akihito and Mirai finally destroys it. Afterwards, Hiroomi, Ayaka and Shizuku show up and bar Mirai from going to Akihito's aid, instead locking him in a cage, with Ayaka explaining of Akihito's youmu half's awakening due to his human half's weakened state. Mirai then horrifically watches as Akihito undergoes a sudden transformation and goes berserk. Desperately trying to keep Akihito contained, the trio are soon overwhelmed by his immense destructive power, with his orange fireballs completely devastating the landscape. Seeing herself in Akihito, Mirai breaks into tears and locks him in a bear hug until his rampaging youmu half calms down. In the aftermath, as Akihito reawakens and despises the devastation he caused, Mirai breaks into tears following his apology. Meanwhile, after observing the struggle, Miroku decides to report back to the Society. Some time later, Mirai and Akihito go out to dinner, with the latter posing the same question she did to him, and Mirai replies with a normal response just as he did for her.

Mirai finally caves in and joins the Literary Club due to Akihito's constant pestering. Afterwards, Mirai, Akihito, Mitsuki and Hiroomi visit the Nase mansion where they run into a departing Miroku. Izumi then confiscates Mirai's Spirit World Warrior license for a month on account of disobeying her orders and going after the Hollow Shadow. Mitsuki then agrees to take Mirai to her part-time job in the hopes that her boss would hire her so she may have income for the next month. While they discuss this at a pancake house, Mitsuki and Mirai also discuss the latter's change of heart to socialization and Akihito's relationship with the Nase clan. Just then, they notice a passerby possessed by a youmu and instantly go after it. Mirai eventually battles and kills the youmu just as Shizuku shows up and treats them to barbeque as thanks. As Mirai notices a poster of the annual Nagatsuki City Lanturn Festival, Mitsuki recalls how she was barred from ever attending due to her duties as a Spirit World Warrior. Afterwards, Mitsuki and Mirai visit Ayaka's shop for the former's part-time job, and Ayaka hires Mirai in addition to forcing her into a photo shoot for extra money. Afterwards, they mention Akihito's depression following his youmu transformation. While they watch the shop, Mirai tries to ask Mitsuki why she refuses to go to the festival to no avail, leaving her with the answer that Spirit World Warriors are alone. However, Mitsuki eventually changes her mind when she recalls how she had set up chartreuse lanterns in her room as a child. Finally, Mirai and Mitsuki run into a surprised Akihito and Hiroomi at the festival, and upon Akihito's confusion at their arrival, Mirai knowingly implies that on the night of the festival none of them have to be alone.

Mirai starts bringing bonsai to the Literary Club meetings and Akihito deduces her gardening hobby to be the true culprit behind her constant financial problems. Having gotten her license back, Mirai gets information from Ayaka about a valuable fruit-type youmu that lurks on their school roof and Mirai immediately runs off without waiting for Ayaka to explain its characteristics. Afterwards, Akihito arrives too late to stop Mirai from confronting the youmu and both become drenched in a yellow noxious-smelling liquid as part of the youmu's defense. That evening, Ai explains that the youmu gets easily distracted by human girls and thus a two-person team would be needed to defeat it, hence Akihito and Mirai pressure Mitsuki into helping. The following day, Mirai showcases some seductive poses in front of the youmu while Mitsuki approaches from behind, however that plan quickly fails and the youmu marks Mitsuki in a much more horrendous pink liquid. As the group contemplates giving up, Hiroomi explains that the last time the youmu was killed, a special song was used to distract it. However, that plan also fails when Mirai turns out to be a terrible singer. As the entire group showers again that day, everyone decides to seek revenge against the youmu for constantly giving them a horrible stink, and hence spend the next week practicing the words and dance choreography for the song. Akihito, Mirai, Mitsuki, Hiroomi and Ai then show off the results of their training and perform the song perfectly in front of the youmu, which drops its guard. Finally, when the group completes their performance, they all come to the horrific realization of failing to assign someone to kill the youmu—at which point it explodes and covers the entire roof in a torrent of yellow liquid.

Sakura recalls Yui's warning of the Hollow Shadow's power while hunting an amphibious youmu. The next day, Shizuku interrupts the Literary Club's usual theatrics to inform them of Sakura's impending transfer to their high school, however Mirai decides not to intervene in the matter. That evening Akihito goes to Sakura's aid when she passes out from fighting a flying youmu and takes her home to tend to her wounds. Here, Sakura explains that her spear grows stronger by devouring youmu crystals and that a mysterious man gave it to her, which she may keep on the condition that she kills Mirai. At that instant, Mirai unexpectedly drops by to return Akihito's phone, forcing the latter to reveal Sakura when Mirai spirals out of control upon noticing the second pair of shoes at his doorstep. The next day, Sakura has a successful transfer despite Akihito's caution. That afternoon, Mirai and Sakura meet at a market alley to settle their score and begin their inevitable battle. Drawing Sakura into the sewers, Mirai explains her realization of revenge being the wrong path and her intention to live for the sake of the Inami sisters. This causes Sakura to lose her fighting resolve at which point the spear attempts to devour her before Mirai stops it. In the aftermath, Sakura admits having lost sight of herself at the chime of Yui's bell necklace; clouding her feelings for Mirai, which she accepts and both reconcile. With the spear now having devoured enough youmu, Miroku collects it with the intention of retrieving the Hollow Shadow's crystal. Finally, Izumi and Mitsuki witness the beginning of a phenomenon called the Calm as it spreads through Nagatsuki City—foreshadowing something known as Beyond the Boundary.

Akihito receives a postcard from Yayoi, warning them of the coming of the Calm as the city starts feeling its effects. Ai and Ayaka explain that during the Calm, all youmu become severely weakened and warns that Akihito could potentially lose his immortality during the period. As the group later heads home, Miroku intercepts Mitsuki and explains that the mirrored phenomenon she witnessed was actually a fraction of a youmu known as the one Beyond the Boundary. Miroku further explains that he was sent to investigate the Nase family's plans for this youmu by the Society and learned that Izumi had saved Mirai from being killed by the Inami clan following Yui's death. Overlooking the golden sunset by the shoreline, Hiroomi then intervenes and attacks Miroku before the latter escapes. Elsewhere, Akihito awakens on the train home following a horrible flashback before Izumi puts him sleep once more. Afterwards, Ayaka decides to watch over Akihito at her shop as he starts feeling the Calm's effects. Afterwards the Calm finally begins at midnight and the Spirit World Warriors of the city including Shizuku and Izumi start slaughtering any and all youmu in sight. Meanwhile, as Hiroomi and Mitsuki try to understand the conflict between their clan and the Society, they learn of Akihito's state and notice the reawakened Hollow Shadow while Sakura manages to convince Mirai to return to Akihito's side. At the same time, Ayaka intercepts Miroku outside her shop following his intention to capture Akihito for the Society and attacks him in her youmu form. However before Ayaka becomes overpowered, Izumi intervenes and stops Miroku's attack. Finally, as Mirai hurries back to the shop, Akihito's youmu half awakens.

Upon arriving at the Shindō shop, Mirai horrifically discovers Akihito in his youmu form. Meanwhile, as Hiroomi and Mitsuki have their hands full with the giant youmu, Izumi faces off against Miroku who escapes when a fireball distracts Izumi. Afterwards, Izumi returns to the shop and attacks Akihito in front of Mirai before he too manages to escape. At the same time, Hiroomi and Mitsuki manage to defeat the large shadow and later rendezvous at Akihito's apartment with Izumi and Mirai. Here, Mirai relays Ayaka's explanation that the Calm had weakened Akihito's human half more than his youmu half, causing the latter to surface. As they track Akihito into the woods, Izumi suggests that Mirai can now kill Akihito with his immortality nullified by Calm since if it ends, his youmu half would likely gain dominance over his body and become unstoppable. The following day, as Mitsuki and Hiroomi ponder on Izumi's ulterior motive, the latter confronts her using Miroku's rationale of manipulating Mirai and that she deliberately weakened Akihito's human half with her freezing barrier, prompting his youmu emergence. However Izumi instead warns him about the Society. Dissatisfied, Hiroomi tries to get Mirai to change her mind from killing Akihito and later enters the Nase family archives where he discovers the shocking revelation of Akihito's youmu half being the one Beyond the Boundary. Just then, as Miroku manages to steal the Hollow Shadow's crystal from the Nase vault, Mirai tracks Akihito's youmu form to a deserted part of the forest under the silver rainclouds and engages him in a furious battle, eventually severely wounding him. Finally, with her heart breaking, Mirai rushes Akihito to deliver the fatal blow.