In regards to the MMORPG Cross Reverie, Sakamoto Takuma boasted an overwhelming strength that was enough for him to be called the Demon King by the other players. One day, he gets summoned to another world with his appearance in the game. There, there are two people that insist, "I am the real summon master." Takuma gets slave-turning magic used for summoned beasts cast on him by the girls -
However, the peculiar ability Magic Reflection was invoked! The ones that were turned to slaves were the girls! Takuma was bewildered. He's the strongest magician but, he doesn't have any communication skills. Panicking, the first words that came out were the ones that he used inside the game role playing the Demon King!? "I'm amazing you say? Of course I am. I am Diablo... The one feared as the Demon King!"
This is the story the Demon King (acting) that would soon inspire the world and his other world adventure that he plunges through with his absolute strength, raise the curtain!

"Hey, boyfriend, how you doing?"

Souta Sakuhara is a first-year high school boy. His first ever girlfriend has just been stolen away from him by a "girlfriend." That girlfriend is Shizuno Mizushima, a tomboy who's also the tallest girl he's ever met, who's now his hated rival in love, taunting him with it. But then…

"Since nobody else wants to be your girlfriend, how about you go out with me?"

She suddenly pins him against the wall! She also started saying, "Give me a month, and I'll make you fall in love with me…… I'm not going to let you go so easily!"

A one-way romantic comedy in which a handsome and beautiful girl will tempt you every day!

Rui, an unremarkable high school student, somehow ends up with Miya, a stunning beauty admired by the entire school, as his girlfriend. However, just then, his childhood friend Ayana, with whom he had grown distant, reappears and starts to shake things up for him. A sexy suspense story of wavering between a childhood friend and a girlfriend!

My name's Karina—or at least, it is now! I used to be a nondescript, run-of-the-mill Japanese salaryman until I was whisked away to a divine realm where the Goddess of Time and Space told me I'd be living a new life in a new world—and as a girl, since apparently she prefers it that way. First she wants me to beat some final boss she has a grudge against, then she takes control of my body to show me how to use my new spatial magic powers in a tutorial fight... Wait, isn't that the final boss I'm supposed to beat?! Less than in a minute into the tutorial and he's dead!? And now she says the world's my oyster. Seriously!?

Official English Light Novel: https://j-novel.club/series/knock-yourself-out-the-goddess-beat-the-final-boss-in-the-tutorial-so-now-i-m-free-to-do-whatever

Nagi Shinonome, known as the "Ice Princess," is a beautiful girl with a cold attitude who does not allow others to get close to her. One day, Souta Minori, who saw her being molested on the train, saved her with all his courage, but the next day she appeared again and said, "I want you to stay by my side." Can Souta continue as friends with the Ice Princess, who only sweetly melts for one person in the world, that is, himself?

After a freak accident involving some lightning winds up zapping him dead, 15-year-old Mochizuki Touya wakes up to find himself face-to-face with God. “I am afraid to say that I have made a bit of a blunder…” laments the old coot. But all is not lost! God says that he can reincarnate Touya into a world of fantasy, and as a bonus, he gets to bring his smartphone along with! So begins Touya’s adventure in a new, anachronistic pseudo-medieval world. Friends! Laughs! Tears! Inexplicable Deus ex Machina! He sets off on a journey full of wonder as he absentmindedly travels from place to place, following whatever goal catches his fancy. The curtains lift on an epic tale of swords, sorcery, and smartphone apps!

Hyakkaou Private Academy. An institution for the privileged with a very peculiar curriculum. You see, when you're the sons and daughters of the wealthiest of the wealthy, it's not athletic prowess or book smarts that keep you ahead. It's reading your opponent, the art of the deal. What better way to hone those skills than with a rigorous curriculum of gambling?
At Hyakkaou Private Academy, the winners live like kings, and the losers are put through the wringer. But when Yumeko Jabami enrolls, she's gonna teach these kids what a high roller really looks like!

Note: Placed 3rd in the DaVinchi x NicoNico Tsugi 2016 Manga Awards.

From Yen Press:

Just a stone´s throw from London lies the manor house of the illustrious Phantomhive earldom and its master, one Ciel Phantomhive. Earl Phantomhive is a giant in the world of commerce, Queen Victoria’s faithful servant and a slip of a twelve-year-old boy.

Fortunately his loyal butler Sebastian is ever at his side, ready to carry out the young master’s wishes. And whether Sebastian is called to save a dinner party gone awry or probe the dark secrets of London’s underbelly, there apparently is nothing Sebastian cannot do. In fact, one might even say Sebastian is too good to be true or at least, too good to be human.

Ishii Kazuki’s life is destroyed after he becomes entangled in the romantic troubles of his friend Amada Teruhito, a boy who is absurdly popular like a romcom protagonist. The situation eventually drives Kazuki to take his own life. However, a miracle occurs, and he finds himself back at the morning of his high school entrance ceremony. In this second life, Kazuki decides to stay inconspicuous, avoid making friends, and live quietly. Yet for some reason, Amada’s childhood friend, the cool beauty called the “Ice Empress,” Hidaka Mikoto, starts approaching him.

The war between Idéal, the country of demon race, and Étoile Kingdom, the country of the human races, had been going on for a long time until a peace overture was offered by the demon lord. Following this, the demonic princess, Lieselotte, was married to the Hero, Schmerz and she'll live in the human world as a hostage of sorts. However, this is just Lieselotte's first step toward her ambition, and her future will be full of hardship that she must overcome...

A fantasy story about Kiska, a boy who is mistreated by the villagers. He manages to survive thanks to his childhood friend Namia, who was the only one by his side. One day, Namia is murdered by three men, and Kiska is accused of the crime and banished to an inescapable class S dungeon. However, he finds himself in a different world where he can use "Save and Reset" to get back on his feet no matter how many times he dies. The story is about Kiska's quest for revenge against those who wronged him and his friend

Saryu, known as the Winter Bear of Tidros for his formidable presence that scatters enemies, suddenly finds himself in an engagement with Lady Shitoen, a noblewoman from a neighboring kingdom whose previous engagement was called off! Starting with a forehead kiss, he's nervous around a woman he's not used to. Her smile makes his heart race, and a glimpse of her chest leaves him flustered. As improper fantasies run wild in his mind, Saryu's rationality is on the verge of collapse?!

I was a public official who worked part-time to survive. I was knocked out by a speeding car while making deliveries in the middle of the night. I have a strong memory of dying prematurely in a hit-and-run. “…I’m Jo Hwi?” At some point, I became the second son of the collapsing Jo Ga-cheol Clan. This family has neither the authority to drop a flying bird nor the power to carry out one’s will. There is only an enormous amount of debt that can annihilate the entire family. There’s only one way out! “Father, please pass the Jo Ga-cheol Clan on to me.” The story of a successful modern man who has to utilize all the knowledge and experience of a public official begins now!!

An unfortunate heroine appeared before me. It seems that this world is an otome game, and I am just an unnamed mob priest who appears briefly in the early stages. I could fulfill my role as a mob and quickly exit the game, but... wait a minute, if things go on like this, the heroine is going to face terrible hardships. To save this cute and kind yet unfortunate heroine, I have no choice but to train her myself!

Banaza, who got summoned to the magic kingdom of Cryroad as a Hero candidate, due to having only the abilities of only a regular citizen, got treated as a disqualified Hero. He, who originally was supposed to be returned to his original world, due to the magic kingdom's mistake, became unable to return to his original world, inevitably has to live in this world. That kind of person, the moment he became Lv2, acquired all skills and magics, and transcended into a super cheat with all ability points broken through the limit! Even so, he does things at his own pace with an easygoing smile.

The story is set in a world where supernatural powers exist through science, and magic exists through religion.

In the story, Touma Kamijou is an ordinary high school boy with terrible academic scores and a power called Imagine Breaker. Imagine Breaker can defeat any other power, but it also undermines Kamijou's own good luck. His Imagine Breaker's immense strength is literally immeasurable, so hapless Kamijou is listed at the supernatural level of 0. He happens to meet a girl in white hanging off his window balcony. The girl says she is being chased by sorcerers, and Kamijou learns that the girl is a Church of England nun whose memories have been forcibly replaced by Index-Librorum-Prohibitorum — the 103,000 forbidden texts of the Church.

A long time ago, a portal to another world was opened, and those who acquired special abilities along with marks began to be called mages. After the incident known as "that day", the first-class mage from Ophion, known as "Blow", has become very famous. One day, he receives a very special mission: to protect the second son of the Artian family, who suffers from being called a "monster" at the magic school "Helios"! Thus, Blow enrolls in Helios under the name "Rood Krisch" to hide his true identity...

“O, Hero!” With that cliched line, Kazuya Souma found himself summoned to another world and his adventure-- did not begin. After he presents his plan to strengthen the country economically and militarily, the king cedes the throne to him and Souma finds himself saddled with ruling the entire nation! What’s more, he’s betrothed to the king’s daughter now?! In order to get the country back on its feet, Souma calls the wise, the talented, and the gifted to his side.Five people gather before the newly crowned Souma. Just what are the many talents and abilities they possess… What path will his outlook as a realist take Souma and the people of his country down? A revolutionary transferred-to-another-world administrative fantasy series starts here!

On days when she is sick, on days when she has a tedious day job, on days when she has regular tests.

On days when she is too lazy to go to school, I am called upon.
I am a convenient substitute for the body of a girl named Sonao Aikawa, and that is me.
I may look exactly the same, but my personality is a little different.
I can't go out freely, I can't even make plans for tomorrow,
I am a replica whose mission is to work for the original.
I was supposed to be a replica, but I fell in love.

A very pure and slightly mysterious "love story" that takes place in a town by the sea.

High school girl Hinako is living a quiet life in a seaside town, but she feels somewhat detached from her friends during the summer months when she is reminded of when her family died years ago. One day, she meets Shiori, a mysterious girl who reminds her of the ocean, especially when it comes to her translucent blue eyes, but Shiori soon reveals that she is actually a mermaid who has been looking for Hinako for a long time.

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Author's twitter: https://mobile.twitter.com/naekawa_sai