Infinite Stratos, also written as , is a Japanese light novel series by Izuru Yumizuru with illustrations provided by Okiura (original MF novels) and (new Overlap novels). As of October 2013, seven volumes have been published by Media Factory under their label. From volume 8 onwards, the novels were published by Overlap under their Overlap Bunko label.
A manga adaptation by Kenji Akahoshi was serialized in the manga magazine Monthly Comic Alive from May 2010 to July 2012 with five volumes published under their Alive Comics imprint. A 12-episode anime television series adaptation produced by Eight Bit aired in Japan between January and March 2011, and an original video animation (OVA) episode was released on December 7, 2011. The anime is licensed by Sentai Filmworks in North America, who released the series in April 2012. A second series aired from October to December 2013.
Plot In the near future, Japanese scientist Tabane Shinonono creates a high-tech powered exoskeleton called "Infinite Stratos" (IS). Possessing technology and combat capabilities far surpassing that of any other arms system, the IS threatens to destabilize the world. Faced with such an overpowered weapon, the world's nations enact the "Alaska Treaty", stating that ISes shall never be used for military combat purposes, and that the existing IS technology must be equally distributed to all nations, to prevent any one nation from dominating the others. However, sometime after the IS was introduced, society has undergone a drastic change. As ISes can only be operated by women, there is a shift in the power balance between men and women, where women now dominate society over men.
Ten years after the IS was initially introduced, the world has entered a new age of peace. However, a 15-year-old Japanese boy named Ichika Orimura changes everything. During an accidental run-in with a hibernating IS suit, it is revealed that he possesses the innate ability to operate an IS—the only male in the world capable of doing so. Seeing his potential, the Japanese government forcibly enrolls the bewildered young man in the prestigious Infinite Stratos Academy, a multicultural academy where IS pilots from all over the world are trained. Thus, he starts a busy high school life surrounded by girls training to become expert IS pilots. While they seem to be enjoying their thrilling school life, the danger of looming threats and enemies is never too far away.
Characters Main characters
Ichika Orimura is a first-year student, class representative, and Student Council Vice President at IS Academy. Raised by his older sister Chifuyu Orimura, a legendary IS pilot, after their parents abandoned them, he regrets her forfeiting the Mondo Grosso tournament to rescue him from Phantom Task. As the only male capable of piloting an IS, he becomes a subject of scientific fascination. While appearing indifferent to the affections of those around him, he avoids romantic entanglements to prevent discord. He pilots the , a prototype fourth-generation IS, later enhanced into with advanced weaponry and mobility. His arsenal includes the , an upgraded version of Chifuyu's weapon.
Houki Shinonono is a first-year student at IS Academy and Ichika Orimura's childhood friend, having been separated from him for six years. Raised in a kendo dojo, she is a national-level kendo champion. Her older sister, Tabane Shinonono, invented the IS, though their relationship is strained after Houki's family was placed under government protection, forcing her to withdraw from a tournament—an event that also severed her early promise with Ichika. She harbors lingering affection for him, often reacting jealously to other girls. Initially without a personal IS, she later pilots the , a fourth-generation melee-focused unit equipped with twin katanas, and . Its signature ability, , replenishes energy upon contact with other IS units.
Cecilia Alcott is a first-year student at IS Academy and the Cadet Representative of the United Kingdom. Born into British aristocracy, she inherited her family's fortune after her parents died in a train accident when she was twelve. To protect her assets, she agreed to attend IS Academy as part of a deal with the British government, who sought data on their third-generation IS. Initially arrogant, she relinquished her position as class representative to Ichika Orimura after recognizing his strength. She pilots the , a long-range sniper IS equipped with remote drones (B.I.T.S. System), the laser rifle, and the blade for close combat.
Lingyin Huang is a first-year student at IS Academy and China's Cadet Representative. A childhood friend of Ichika Orimura, she developed feelings for him after he defended her from bullies. Their friendship becomes strained when Ichika forgets a childhood promise tied to her cooking skills. Nicknamed , she comes from a family that ran a Chinese restaurant before her parents' divorce. She pilots the , a short-to-medium range IS equipped with shoulder cannons and the , twin blades that combine into a naginata-like weapon.
Charlotte Dunois is a first-year student at IS Academy and France's Cadet Representative. Initially posing as , a male student, she was assigned as Ichika Orimura's roommate to gather data on his IS capabilities. Her true gender is revealed when Ichika accidentally sees her showering. After learning her father's corporation exploited her for espionage, Ichika protects her, leading to her developing feelings for him. She pilots the , a versatile 2nd-generation IS with interchangeable weapons and Ignition Boost capability. Trained to pose as male, she uses the pronoun . Later, she becomes roommates with Laura Bodewig.
Laura Bodewig is a first-year student at IS Academy and Germany's genetically-engineered Cadet Representative. As commander of the special forces unit , she bears distinctive cybernetic enhancements including a glowing yellow eye concealed by an eyepatch. Originally sent to confront Ichika Orimura over his sister's withdrawal from Mondo Grosso, she later develops feelings for him after he calms her during a berserk state caused by her IS's malfunction. She pilots the , an artillery-type IS equipped with restraint tethers, a railgun, and an Active Inertial Canceller. Following these events, she declares herself Ichika's protector, referring to him as her "bride" due to cultural misunderstanding.
Tatenashi Sarashiki is the student council president of IS Academy and Russia's IS Representative. As the 17th leader of the Sarashiki family—a secret organization opposing Phantom Task—she is also the school's strongest pilot. After the Silver Gospel incident, she becomes Ichika Orimura's protector and roommate, often teasing him flirtatiously. She pilots the IS. When Ichika helps activate her sister Kanzashi's IS and saves her from American soldiers, she reveals her true name , developing genuine romantic feelings for him. Her playful demeanor hides her serious combat skills and family responsibilities.
Kanzashi Sarashiki is Japan's IS Representative and Tatenashi's younger sister. Despite her position, she initially lacks a personal IS after development of her unit was delayed in favor of Ichika's Byakushiki, creating unwarranted resentment toward him. An anime enthusiast who struggles with self-doubt when compared to her accomplished sister, she eventually receives her operational IS through Ichika's assistance. This experience helps her overcome her inferiority complex and develop romantic feelings for Ichika, while also gaining new appreciation for her own abilities separate from her sister's shadow.
IS Academy staff
Chifuyu Orimura is Ichika's 24-year-old sister and his homeroom teacher at IS Academy. A former legendary IS pilot who once wielded the Yukihira blade (now inherited by Ichika), she retired to raise her brother after their parents abandoned them. Though outwardly indifferent, she deeply cares for Ichika, enrolling him in the academy to protect him from foreign interests. She previously piloted the prototype that famously defended Japan against 2,341 simultaneous missile attacks. Currently using the Kurezakura IS, Chifuyu shares a mysterious past with Tabane Shinonono, Houki's sister, which explains the younger siblings' childhood connection.
Maya Yamada serves as the substitute instructor for Ichika's class at IS Academy. A former Japanese IS Representative Cadet, she demonstrates exceptional combat skills by defeating both Cecilia Alcott and Lingyin Huang simultaneously during a training exercise—overcoming their personal IS units while piloting only a standard Rafale Revive mass-production model.
Phantom Task
Madoka Orimura is the long-lost younger twin sister of Chifuyu and Ichika, bearing a striking resemblance to Chifuyu. As the leader of Phantom Task under the codename M, she harbors unresolved resentment toward her siblings. She pilots two advanced IS units: the Silent Zephyrs, a superior variant of Cecilia Alcott's Blue Tears, and later the Black Knight, provided by Tabane Shinonono. It is later discovered that Madoka is not biologically human but was artificially created using Chifuyu's genetic material, intended to serve as her successor. Her motives remain conflicted, torn between her engineered purpose and familial ties.
Squall leads Phantom Task's combat squad as a composed yet formidable operative. She pilots the unique Golden Dawn IS, displaying exceptional combat reflexes and tactical restraint—notably preventing Madoka from excessive violence during operations. While maintaining a polite demeanor, she demonstrates ruthless efficiency when necessary. Her primary mission involves gathering combat data on Ichika Orimura's Byakushiki in its White Knight configuration, though her ultimate objectives remain undisclosed. The technical specifications and generation classification of her Golden Dawn IS are unverified.
Autumn is an impulsive Phantom Task operative who attempted to steal Ichika Orimura's Byakushiki during the IS Academy anniversary using a specialized "Remover" device, narrowly thwarted by Tatenashi Sarashiki's intervention. She pilots Arachne, a stolen second-generation American IS featuring an eight-legged mobility system. Notably aggressive in combat, Autumn displays uncharacteristic vulnerability around squad leader Squall, with behavior suggesting romantic attachment. Her tactical approach contrasts with Phantom Task's typically measured operations, often prioritizing direct confrontation over subtlety.
Other characters
Tabane Shinonono is the brilliant but elusive creator of IS technology and Houki's estranged older sister. As the world's most wanted individual due to her knowledge, she maintains close ties only with Chifuyu Orimura and the younger generation—Ichika and Houki—while displaying open disdain for others. Her cheerful demeanor masks formidable combat skills, demonstrated when she effortlessly countered three Phantom Task operatives. Though responsible for Ichika's initial IS compatibility through system modifications, she claims no knowledge of Byakushiki's unique movements. The rabbit motifs in her appearance reflect an eccentric personality that belies her dangerous reputation. Her past actions regarding IS development continue to affect both Houki and Ichika's lives.
Clarissa Harfouch serves as deputy commander of Schwarzer Hase, Germany's IS special forces, and pilots the . Like Laura Bodewig, she wears an eyepatch and shares an interest in Japanese media, though her anime-influenced understanding of the culture often proves unreliable when instructing Laura.
Natasha Fairs serves as the United States' IS Representative Cadet. She was the test pilot for the experimental , which went berserk until stopped by Ichika Orimura and his allies. In gratitude, she kisses Ichika—a gesture that provokes jealousy among his peers.