As a six year old, Rintaro is diagnosed with Henisei Tashu Ijou Syndrome (also known as Hentai Syndrome), a disease that could kill him if he gets sexually aroused. To save him and provide a way for him to live as normal a life as possible, his father teaches him the ways to control his body and mind for ten years in the mountains, with the martial art of the Koei Sougetsu. When he's 16 he chooses to enroll Nangokuren High School, which he assumed to be the biggest all-boys school in the country but is actually the biggest all-girls school that has just gone coed.

On his first day he stumbles upon a large scale battle and learns that the first rule of the school is that it "Abides the Law of Nature" which has turned the campus into a war zone-like environment. Rintaro now sees transferring out as his mission, but will it be that easy now that he's caught the eye of the 3 "Dragons", the bodacious female leaders of the three biggest factions around?

Meet Handa Sei, a second-year in high school. Occupation: calligrapher. Admired by the whole school for his cool charisma, Handa is, in fact, naturally negative and sincerely believes that the whole school hates him!

A comedy about the misunderstandings of adolescence and mistaken impressions.

This manga follows the story of 7 high school students, 3 boys and 4 girls in year 1 class A. Their not-so-ordinary ways of thinking and everyday lives are loaded with comedy, dirty jokes. At times, debating about how to use a toilet, at other times, risking their lives over growing body hair in unusual places!

Crossover between Ore Monogatari!! and Nisekoi.

A powerful grand wizard named, “Raim” reappears after a millennium because of a failed experiment. While sets out to regain his lost tower, he meets “are” and “ere” who have been trafficked as slaves... a combination of a weird grand magician who only uses his wits to make money and the cute, lovable brother and sister of the miao tribe! Their endless adventure is beginning to unfold. Editorial staff’s comment Will Raim be able to regain his lost tower?! 

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+ This is another ambitious work of Sung San Young, The Gamer
+ Tower of God
+ The God of High School

In the land of Glengard, the realm's 666th Demon King, Fienalia Glengard Flamveil...is bored. With no challenges to excite her and all of humanity long since subjugated, she's off to find a new worldany world!to conquer...and it just so happens that Earth is next on the hit list! But when "Ena-sama" meets Kento Sugitani, an aspiring manga artist, it seems she might have found a new hobby more interesting than world domination. What is a demon lord to do but enroll in a manga school herself?!

(Source: Yen Press)

From Easy Going Scans:
Before, magic filled up the world, and then magic suddenly disappeared, from everywhere.
Magicians can’t perform magic anymore, so now these formerly powerful, now talentless ones are looked down upon by warriors and practically everyone else. But two people in the world are able to perform magic after its disappearance, a power-hungry wizard and a young boy who loses everything he holds dear.
Follow Melrose and his companions in their adventures as they try to solve this Dark Air mystery.

A few years ago, while on a journey to defeat The Demon King, the hero disappeared, leaving only his holy sword behind. And so, a new hero arises...

Hida Kizuna possesses the HHG (Heart Hybrid Gear) ability, but it is not strong enough to make him particularly important. His older sister calls him to transfer to a strategic defense school, where many of the students (many of which are large-breasted girls) use their HHG abilities to fight invaders from another world while wearing extremely skimpy pilot outfits. Kizuna's fighting ability doesn't measure up, but his sister has another plan-- apparently having erotic experiences with Kizuna will allow the girls to replenish their energy or power-up. It looks like his new school life is going to be full of embarrassment.

A Boy from an alien planet learns that he is not of that planet. He moves to Earth because of an “immigration project” and now must learn to live among the humans in the scariest place on Earth, Seoul Korea.

Set during the Goryeo military regime, a hero that arises from a slave to be reborn as a general.

Enma's daughter Batsu is looking for help to take down some demons. And who does she turn to...? Normal teenager Takuan! 

Based on Valkyrie Drive: Bhikkhuni PS Vita game.

"A couple of elves, a gnome and an android walk into a bar… Ranial, Thame, Ian and Math, four strangers brought together by circumstance, set off on a series of cybernetic adventures in the wake of a war that has left their world a post-apocalyptic fantasy wasteland. Words by Sam Machado, Art by Cynthia Sousa (Theamat), Colors/Letters by Amanda Sousa Machado, Created by Bradley Mason."

From Storm in Heaven:

Kyu's greatest desire is to become a detective. To fulfill his wish, he goes to take the entrance exam to get into the detective school run by Dan Morihiko, one of the most famous detectives ever! At the exam he meets Megu, Kinta, Kazuma, and Ryu as they all try to pass the grueling three-part exam. Kyu wants to solve mysteries, and he gets his wish: his first real case appears in the midst of the exam!

An Onmyodo School Fantasy of a Failing Private Onmyo Academy Student!!
Tsuchimikado Harutora was born into a prestigious Onmyoji family, but he can't see "spirit energy". Therefore, he's been enjoying a peaceful daily life with his friends at an Onmyo branch school. One day, his childhood friend Tsuchimikado Natsume, heir to the head family, suddenly appears. Will this cause his destiny spring into motion!?

Failed on his job-hunting, shut-in Sagara Kurohiko went to the mountain on the day of a typhoon where he is struck by lightning and dies. But he is still alive, in a strange land with a great holy tree. To his surprise, his physique has rejuvenated to when he was teen. Brought to the academy near the tree, he is soon suspected as a spy from another country, and was brought to the headmaster. An accident happened on the way, which enraged the headmaster. Before Kurohiko can get blasted by magic, his eyes laid upon an old parchment. He took it and read the contents. Suddenly four holes appeared and black chains came out from each of it, binding the headmaster. It is then revealed that Kurohiko just recited an incantation of "Forbidden Art," an art which is extremely powerful from a legend. Apparently, no one has been able to decipher the contents of the scroll, which makes Kurohiko the only current Forbidden Spellcaster. Sparked by this, the headmaster offers Kurohiko to attend the academy.

The setting of Devil Survivor 2 spans the whole country of Japan. It tells the story of Japanese high-school students who receive emails from a website foretelling their friend's deaths. Mysterious creatures invade the country, and the students enter a pact, enabling them to summon demons from their cell phones with a special Devil Summoning App.