Hyoudou Issei is an ordinary yet lecherous high-school student who is killed by his girlfriend, Amano Yuuma, during their first date. Yuma is revealed to be a fallen angel named Reinare who was sent on a mission to eliminate divine weapons. Issei is later reincarnated as a demon by his senpai Rias Gremory; in return, he will serve under Rias to fight against the fallen angels.

The protagonist is a guy who is among the stupidest of the stupidest in the school. In this school your grades can, under the supervision of teachers, take a virtual form to do battle! However, if you leave an examination midway, you get zero marks. A bright and cute girl, Mizuki Himeji, had a high fever during her examination. Despite her potential to be the second highest scorer in the level, she obtained zero marks for having left due to her illness and is thus banished to the worst class, Class F.
Grades mean nearly everything. For Class A: They have a smart-looking teacher, a plasma TV as big as the entire wall as their blackboard, personal laptops, personal air-conditioners, refrigerators, adjustable seats and all kinds of different appliances. Within the refrigerator, there are all kinds of drinks and snacks. Their ceiling is made of glass, the wall lets them put up high-class drawings and plants.
As for Class F (the worst class): They have Japanese desks and seat paddings. Their blackboard is dirty and there's even no chalk! Someone complains the legs of his desk are broken, so the teacher asks, "Didn't we distribute some glue to stick wood together? Glue it back yourself later." Another one complains the wind is blowing in from the broken window. The teacher says, "I got it. I'll apply for plastic bags and super-glue to fix it later." There are spider webs everywhere, not a patch of the wall is clean. A unique moldy smell spreads across the entire room; it must be from the old tatamis used to tile the floor. Welcome to Class F.
The protagonist feels displeased at such an arrangement; he seeks help from his friends to try to make a change through invoking war! And they devise all kinds of plans to try to beat the famous Class A, scheming to get Class A's classroom and equipment if they win.

Hachimitsu Private Academy was a revered and elite all-girls’ boarding school on the outskirts of Tokyo…once upon a time. But with the new school year comes a revision to school policy: Boys are to be admitted into the student body for the first time ever. But on his first day at Hachimitsu, Kiyoshi Fujino discovers that he’s one of only five boys enrolled at the school. Their numbers overwhelmed by the thousand girls in the student body, is it heaven or hell that awaits these five (un)fortunates?!

Note: Was one of two winners of the Best General Manga award alongside Gurazeni at the 37th Kodansha Manga Award in 2013.

Tezuka Kanna, 15, is a girl who loves manga. For that reason, she specifically enrolls in a course for manga in Tokiwa High School as a freshman! No one knows though, that she is already a debuting manga artist. ...But wait, what's this?! Three handsome guys suddenly appear, and what's more they know!!! Kanna (God) vs. Those Guys (Devils)!!! What would happen next?!

Taichi Yamada is what you would call a fan but he is not just any fan, he is a fan of Kokoro Shiina, a gravure model. Maybe it was fate that brought them together that day but Taichi met Kokoro when she literally fell from the sky. Waking up in the hospital, he begins to see Kokoro's spirit and after roaming the hospital premises a "shinigami" arrives to take Kokoro to the underworld. Is this the end for Kokoro? What will Taichi do to save his beloved idol?!

Seven years ago, Yuto's older sister vanished through a mysterious door, leaving him with only a necklace. Now he has once again seen that same door, and watched two mysterious girls (Saya and Hina) go through it. Eager for clues about his sister's disappearance, he and his pet cat follow them through. However, he soon finds there's a reason his sister wouldn't let him come with her. In the deadly world on the other side of the door, his ignorance leads to tragedy. Now Saya insists that he travel through the door once again, to search for a way to retrieve the lives that he caused to be lost during his first journey.

From Seven Seas:

Welcome to Ansullivan Dragonar Academy, a school with a difference: the students are dragon riders, each contracted with their own personal dragon. Ash Blake has the unique ability to ride anyone's dragon, but he's been waiting for what feels like forever for his own dragon to be born. He's thrilled when his dragon, Eco, finally appears--but she inexplicably takes the form of a beautiful human girl.

Eco's peculiar appearance is only the first unusual thing Ash faces. His life is about to become a whirlwind of spies, dragon races, and unexpected attention from both the proud Princess Sylvia and the beautiful president of the student council, Rebecca. All Ash wants is to acclimate Eco to the world, but someone out there wants his strange dragon on the dissecting table!

The first year middle school Student Council Chairpersons (iincho) come from different elementary schools and different backgrounds. These six cute, glasses-wearing middle school girls often fight, but they have a common enemy in the sexual-harassing Student Council President. Will they be able to do their job without being distracted by infighting or thwarted by the controlling Student Council President?

For some unknown reason, which is apparently connected to something called the "World Ninja Record," high school freshman Yaezaka Tatsuko is being targeted by ninjas. Moreover, all of these ninjas are representative "Iga" from various countries. Thanks to her childhood friend, Japan's Iga, Tatsuko is an expert in defeating ninjas, however, she might not be able to overcome the craftiness of America's Iga.

Even though this is a sequel to To Love-Ru, all of our main characters make an appearance along with some new additions. Rito continues to be caught in over the top uncensored ecchi scenarios. The alien Deviluke sisters still use their unique abilities to grab Rito's love confession. Nana and Momo have transferred into the school and meet Mea, who seems to be a worry free and joyful girl. Momo in particular wants to share Rito and create a harem for him. While scheming her plan, she confronts Golden Darkness also known as Yami. They are interrupted by possessed students who begin to fight with abnormal strength. Now the new plot line appears as a mysterious person who's in control of the students tests Yami's assassination skills. Who is this new enemy?

N/A

For as long as she's been aware, the heroine, without a single relative, lived under the care of the state. Both of her parents' faces were unknown to her.

In front of this heroine, a boy appeared.

The boy's name was "Hikaru." It appeared that he was the heroine's twin brother, separated at birth. He had a proposal for the heroine: "Could you go to school in my place?"

The heroine was shocked by this crazy suggestion.

Furthermore this was an all-boys schoolthe only high school in the prefecture for delinquents.

From MangaHelpers:
Mikado Shuuji is just an ordinary guy, but he has a very unusual knife that he uses for cooking. It's actually a famous short sword that marks its owner as the head of the ninjas, and now there are hot ninja girls coming after him to take it back. Hinamori Botan is one of those hot ninja girls, but her efforts to attack Shuuji mostly end up inadvertently stripping her. After she concludes that she does not want to steal the sword and kill Shuuji, she ends up deciding to serve him as a ninja instead. Now she must protect him from the other ninja that come to claim his sword and his life.

Serinuma Kae is a chubby second-year high schooler and an avid fujoshi who secretly ships her classmates, Igarashi-kun and Nanashima-kun. The death of her favorite anime character causes her to become stressed and lose weight rapidly. Now that Serinuma has become an attractive girl to her classmates, her snarky kouhai Shinomiya-kun, and her senpai Mutsumi-senpai. How is she going to deal with them...with her constant BL-filled, fujoshi mind?!

Won the 40th Kodansha Manga Award for Shoujo in 2016.

Fujimura is a loner delinquent at his school. Feared by his classmates since the first day of high school, he's had no friends and usually ditches class. But even his standoffish nature can't hold up when a class representative with a few screws loose comes after him! And two more class representatives. They're a few cards short of a full deck too. (Actually, he's more like the tsukkomi in a world of boke.)

From Manga Abyss:

My name is Kohinata An. My parents went overseas to work and left me to live with my grandma. However, she was hospitalized all of a sudden, leaving me as the manager of her lodging house! Furthermore, there are three cool guys lodging there! Ba-dump. Ba-dump. But one of these three guys, Ryuu-kun, seems to hate me for some reason... What for--?!

A small chapter like memoirs of a boy and the girls who are in his like. Classic lazy good for nothing with 3 hot school chicks = GOLD!

In a world where humans co-exist with Juujin (literally: "beastmen"), genetically mutated animals that have remarkably human-like features with the exceptions of extremities such as tails and ears, Juujin are often found as laborers in the work force or raised in households as pets. That is until a new kind of Juujin appears-- Evolutions, EVOs for short. These Juujin have special magic-like powers that they are using against the human race.
Peke, one such EVO, has been raised with her master Yamato Yamamoto. Yamato's mother works for the Health Care Center-- the only agency with jurisdiction over the Juujin, and has developed a special collar that can seal the EVOs' powers. Having used this collar to control Peke's own powers from going berserk, Peke must now release this power to fight and capture the rampaging EVOs to save humanity and to win her master's love.