Manga Like It Was a Mistake, Grand Duke!

In the series "Kami nomi zo Shiru Sekai," high school student Keima Katsuragi is known online as the "God of Conquest" for his unmatched success in dating simulation games. He finds real-life interactions with actual girls frustrating and inferior to his virtual experiences. One day during his break from cleaning duties, Keima encounters a peculiar challenge to win over a real girl. Curious, he accepts the offer, which unexpectedly summons Elucia "Elsie" de Lute Ima, a demon sent from hell to reclaim rogue spirits that have attached themselves to human females. Keima tries to escape, but Elsie tells him that breaking their newly established contract would result in his death. With no choice, Keima uses his gaming skills and knowledge of dating simulations to navigate the complex world of real relationships and capture the rogue spirits.

Negi Springfield, a ten-year-old wizard who recently graduated from Merdiana Magic Academy in Wales, has two primary objectives: locating his missing father, the legendary Thousand Master, and earning the title of Magister Magi, a wizard whose purpose is to aid the non-magical world. As his final assignment, he is sent to teach English at a Japanese middle school. Upon his arrival, Negi is surprised to discover that he is responsible for a homeroom class of thirty-one girls. One of his students, Asuna Kagurazaka, accidentally discovers his magical identity. With this secret now exposed, Negi must prevent it from spreading further while dealing with various magical threats emerging both inside and outside Mahora Academy, all while continuing his search for his father.

Several months after the events of the first season, Youkai Academy has been rebuilt and a new semester begins. Tsukune and his companions return, having grown stronger. The true nature of Anti-Thesis is revealed, along with new enemies and a threat far more dangerous than anything they have faced before. Tsukune struggles with the monster awakening inside him. With guidance from Moka, Mizore, Kurumu, Ruby, and Yukari, he trains to control his vampire heritage and gain the power needed to protect those close to him. The second season explores more of the girls' backgrounds and their family connections. New trials await, along with new allies who will join their side. Together, they seek to uncover the secrets behind Moka's rosary and her bloodline.

In Tomoeda Elementary School, Sakura Kinomoto, a cheerful and kind-hearted 10-year-old starting her fourth-grade year, discovers a mysterious book called The Clow on her father's bookshelf one day. When she opens it, a small, winged creature named Keroberos emerges, speaking with an Osaka accent. He introduces himself as the Creature of the Seal, the guardian of the powerful Clow Cards inside the book. However, the Clow Cards have already escaped from their confinement. It now becomes Sakura's responsibility to recapture them before they cause chaos throughout Tomoeda. With guidance from her new companion, whom she calls "Kero," and support from her best friend Tomoyo Daidouji, Sakura uses a magical bird-shaped key and her newly awakened powers as the Cardcaptor to protect the town and preserve its peace.

Asahi Kuromine is famous for being completely incapable of lying. One day, on his way back home, he accidentally discovers a shocking truth: his love interest, Youko Shiragami, is actually a vampire. Can Asahi manage to protect her secret? This is a funny, awkward, and truly unique vampire romantic comedy.

In "Trinity Seven: The Seven Magicians," Arata Kasuga lives a normal life with his cousin Hijiri until she disappears because of a mysterious event known as the "Breakdown Phenomenon." Resolved to stop this phenomenon and be with Hijiri again, Arata enters Royal Biblia Academy. With help from seven girls who are each skilled in a distinct type of magic, Arata starts a journey where anything appears possible. This shounen series mixes romance, comedy, and serious magical adventures together.

At twelve years old, Mitsuki Kouyama is diagnosed with a rare form of throat cancer, sarcoma. Faced with the option to remove her vocal cords and potentially cure the disease, she refuses, driven by her dream to become a pop singer and honor a promise made to her childhood sweetheart, Eichi Sakurai, who moved to America. As her condition deteriorates, Mitsuki accepts her grim prognosis. One day, while escaping from her grandmother's house—where music is forbidden—to attend an audition, Mitsuki encounters two shinigami, Takuto Kira and Meroko Yui. Recognizing that she can see them, they inform her that she has only a year left to live. Moved by her circumstances, Takuto offers Mitsuki a way to pursue her dreams by transforming her into a healthy sixteen-year-old. With renewed hope, she successfully joins Seed Records and debuts under the stage name Full Moon, determined to fulfill her musical aspirations before her time runs out. Included one-shot: Volume 2: Full Moon wo Sagashite

Lusty teenager Issei Hyoudou's life takes a sudden turn when a gorgeous girl named Yuuma Amano asks him out. However, her true nature as a fallen angel is revealed when she tries to kill him. His life is saved at the last moment by senior Rias Gremory, who reveals her own secret—that she is a devil. To protect Issei, she turns him into a devil under her command. With this new lease on life, Issei becomes involved in the supernatural world. He joins the school's Occult Research Club, where he meets other devils and learns to navigate a complex existence filled with both devils and fallen angels. In his quest for strength, Issei must discover his true priorities and realize that a devil's path is anything but straightforward.

Takuma was an ordinary gamer, but a twist of fate pulls him into another world—in the body of a demon lord! And nobody is more frightened by this than Takuma himself. He possesses great power, but he's completely out of his depth. So he decides to play the part of the monster he resembles, and accidentally acquires two gorgeous slaves: a curvaceous elf and a cat-eared girl. None of them wished for this situation, but they must learn to work together if they want to survive.

In "The Ice Guy and the Cool Girl," Himuro is an office worker belonging to a supernatural race with special abilities. Whenever he focuses intensely, he inadvertently freezes his surroundings. Despite his power to turn things to ice, Himuro is gentle-natured and has a fondness for flowers and cats, though he keeps his distance from them because of his abilities. He develops feelings for Fuyutsuki, a calm coworker who often provides straightforward solutions to his unusual problems. Each time she assists him, emotional turmoil stirs within Himuro, frequently resulting in actual snowfall throughout the office. Due to these recurring snow incidents, everyone except Fuyutsuki is aware of Himuro's affections. Nonetheless, driven by deep devotion and resolve, Himuro is determined to win her heart no matter what.

Witches suddenly declare war on humanity, unleashing chaos that devastates two-thirds of the planet. These witches summon entities known as "Supporters," which they use to assault human settlements, though their motives stay ambiguous. People born with the ability to fight the witches are banded together as Witch Hunters by the remaining population. Among these hunters, Tasha Godspell is notable, earning the nickname "The Marksman," and is accompanied by a Supporter resembling a "Jack-O-Lantern." Though Tasha fights against the witches, he finds it hard to truly despise them.

Catarina Claes, the eight-year-old daughter of a duke, hits her head one day and recovers memories from a past life. She comes to a horrifying realization—she is now in a world resembling an otome game she once played, and she occupies the role of the main villain. In every possible conclusion, whether exile or death, she is met with a terrible end. Using her knowledge of how the game unfolds, Catarina must do whatever it takes to change her fate. Whether she cultivates her skills as a farmer or befriends every character that comes her way, nothing is ever too much for her to handle. As the years go on, everything seems to be going as planned. However, Catarina realizes she made a mistake in her previous life—she never actually finished the game before death. A new, secret route may prove to be her undoing.

In "Shinobi Life," Beni, a spirited and defiant young woman, remains unconcerned about her own destiny as long as it brings shame to her arrogant father. One day, she encounters Kagetora, a ninja who falls from the sky and swears absolute loyalty to her as her guardian. Having time-traveled from a distant past, Kagetora is committed to protecting Princess Beni. Yet, he does not realize that this Beni is not the true princess. The narrative examines if true love and dedication can persist across centuries in the tumultuous modern era.

Airi Hoshina lives by a strict schedule, convinced that perfect timing will secure her ideal future: a loving husband and a happy family. Her orderly world is upended when a tiny boy suddenly emerges from her hand mirror. He introduces himself as Aram Astale Ei Daemonia Eucalystia, the young prince of Astale, who fled his own realm to escape a curse. His escape accidentally carried him through Airi's mirror. Though he avoided the curse's full effect—which would have turned him into an old man—he now ages to 17 whenever night falls. The only way to break the spell is a kiss from his destined maiden. Despite Airi's determination to find her own true love, Aram is convinced she is his soulmate, much to her frustration.

In "Beware the Villainess!", Melissa Foddebrat rejects the usual destiny of a villainess in a story, sidestepping both execution and a miserable existence. Known for her beauty and sharp tongue, her childish behavior only irritates those around her. However, a modern Korean woman is reborn into Melissa’s body, transforming her into the daughter of a wealthy duke in the world of a novel she once read. Determined to avoid the villainess role, Melissa aims for a life of ease. To achieve this, she must end her engagement to the promiscuous and dull-witted crown prince. Yet, breaking free from this unwanted union proves more difficult than expected, as the prince stubbornly clings to their relationship. Melissa draws on the strength from her previous life to overcome the obstacles in her new one and pursue her true goals.

Following a long and arduous journey, the Hero finally reaches the Dark Lady's castle, only to be met with an unexpected plea for cooperation. The Hero explains that the ongoing conflict between demons and humans has resulted in countless deaths and widespread suffering. The Demon Queen, however, counters this by arguing that the war has actually served to unify human society, citing evidence of increased population, productivity, economic growth, and overall societal well-being. She further claims that ending the war could trigger a civil war, leading to even greater chaos and loss of life. Convinced that lasting peace can only be achieved through an alliance with the Dark Lady, the Hero decides to support her goals. Included one-shot: Volume 12: Level Hero!

On a typical Saturday evening, Keiichi Morisato is alone in his dorm room when he accidentally dials a wrong number, connecting him to the Goddess Technical Assistance Hotline. A deity named Belldandy appears to grant him a single wish, anything at all. Belldandy explains that Keiichi can ask for virtually anything in the world. Despite his skepticism, Keiichi decides to test her by wishing for Belldandy to remain with him forever, thinking it would expose her lack of true power. This wish almost causes a rift in the fabric of reality but is eventually granted. Yet, this leads to unforeseen complications; notably, Keiichi resides in a male-only dormitory. His roommates' discovery of a woman in their midst results in Keiichi being evicted. Additionally, the wish triggers various unexpected outcomes, such as a motorcycle spontaneously repairing itself to allow Keiichi and Belldandy to travel together when faced with separation.

After Sakura Kinomoto successfully captures and transforms the Clow Cards into Sakura Cards, she believes her days as a Cardcaptor are finished. However, on her way to her first day at Tomoeda Middle School, she is happily surprised to find Shaoran Li, who announces his permanent move to Tomoeda and will be attending the same school. Despite this happiness, Sakura has a peculiar dream that night, where she is encircled by translucent cards and meets a cloaked enigma. Waking up, she discovers her Sakura Cards have indeed turned clear—her dream has come true. With recurring visions, a new staff, and encounters with unknown cards, Sakura must resume her role as Cardcaptor, alongside her guardians and friends, embarking on a fresh adventure.

Ikki Kurogane is a Blazer, someone who can materialize his soul into a weapon, but he is notably inept with magic, making him a complete underachiever among his peers. Known as the "Worst One," he seeks to offset his magical shortcomings by refining his swordsmanship and pursuing the path of a Mage-Knight. Stella Vermillion, the second princess of the Vermillion Empire, is a highly accomplished Rank A Blazer who has never suffered defeat. Driven by a relentless desire for formidable opponents to test her abilities, she travels to Japan with the goal of mastering the way of the Mage-Knight. Their paths converge at Hagun Academy, one of Japan's premier Mage-Knight institutions. Both share an aspiration to achieve greatness as exceptional Mage-Knights through dedication and skill. Yet, to make this dream a reality, they must first face each other in the final round of the Seven Stars Battle Festival. This brutal competition pits the top student knights from all seven Japanese schools against one another, with the winner earning the prestigious title of Seven Stars King. Can Ikki and Stella overcome the trials posed by the most powerful Blazers and reach the highest levels of knighthood?

Having spent her entire life in confinement, sixteen-year-old Emma finally makes it to the capital city of Hawk Eye. Upon her arrival, every male in the city, including the king, becomes instantly captivated by her, putting her at risk of forced marriage. A young and exceptionally talented sorcerer named Shion comes to her rescue. Despite having encountered each other previously, Emma has no recollection of Shion. Shion discloses that Emma is cursed with the Echidna, a dark magic that emerges every five centuries, manifesting in a girl whose heart is filled with overwhelming dark energy capable of world destruction. With such power, one could conquer the globe, and Shion cautions Emma that she will be pursued by those seeking to seize her heart. However, there exists a ritual to free her from the Echidna's curse, which requires a challenging and lengthy journey. The initial step of this ritual involves Emma and Shion getting married. Included one-shot: Volume 8: Karakuri Link

Amid the unending conflict between the Northern and Southern Kingdoms, the prospect of peace appears unattainable. Seeking to end the war, Prince Johane of the North and Princess Euda of the South announce their mutual affection, aiming for their marriage to foster harmony. In reality, however, the two despise being together.

A hero once summoned to another world saved that world. However, he fell into a "trap" and was forcibly returned to his original world. On top of that, he had to start over as a baby... This is the story of that former hero's crazy journey in another world after being reincarnated into a slightly gloomy high school student, only to be "resummoned" back to that same world! There's a lot of room to work with when it's the second time around.

In contemporary Japan, where ninjas are expected to embody unwavering loyalty to their lords, high school student Rekka Hanabishi—who identifies as a ninja—struggles to uphold this tradition. His perspective changes after he rescues Yanagi Sakoshita, a gentle-hearted girl, from a group of bullies. Rekka then declares Yanagi as his rightful master and vows to protect her. To mark their new bond, each reveals their hidden abilities: Yanagi possesses the power to heal swiftly, while Rekka can ignite flames with a mere snap. However, their secret is soon uncovered by a mysterious figure named Kage Houshi, who is aware of their unique talents. She demands that Rekka be returned to her, asserting that he alone has the power to end her life. Despite her threats, Kage Houshi departs without further confrontation. Believing the danger has passed, Rekka and Yanagi resume their normal lives, unaware of the ancient ninja conspiracy that will soon threaten not only themselves but also their friends.

In a world where immortal gods dwell alongside immensely powerful suras, and humans are caught in the conflict between them, a girl named Kubera—whose name mirrors that of a deity—is born under a prophecy foretelling great change. Her peaceful village is consumed by fire, but she is rescued by a mysterious sorcerer named Asha. Together, they embark on a journey for truth and retribution.