Guns Girl SchoolDayZ EX is a special comic series depicting the stories behind the world of the popular game, Guns Girl SchoolDayZ. It also includes the various backstories of the characters in the game.

http://www.u17.com/comic/90459.html

When the black blade roars, all who stand in its path shall be torn asunder…! What is it that Koinzell, the mysterious young boy who wields the sword with such exceptional skill, desires? The fight against the “Lances of Betrayal,” who were thought to have been defeated by the Seven Heroes, begins--And at battle’s end, only the shocking truth will remain amid the pools of blood.

Cyborg 009 Conclusion - God's War is intended to be a proper conclusion to the original Cyborg 009 series. The manga is illustrated by Masato Hayase and based on Ishinomori's original concept notes, sketches, and a novel draft, all of which had been gathered by his son, Jo Onodera.

Set in a Western Medieval-like place during times of war, Eleonora "Ellen" Viltaria, one of the Vanadis of Zhcted, leads the battle into Brune. There are, in fact, seven Vanadis, named for having each received a powerful weapon from the dragon to individually reign over seven territories. The power of the Vanadis invokes dread and fear from their enemies. An earl in the service of the country of Brune, a young archer by the name of Tigre, experienced the Vanadis's power firsthand after being defeated on the battlefield by Ellen. However, Ellen chose to spare his life after witnessing his skills, but in exchange, he is asked to serve her.

For 500 years, people have been unable to enter “The Forbidden Continent” in the Southern Hemisphere. Mankind’s first successful voyage, the research ship “Pandora”, has returned. People from around the world gather to try and catch a glimpse; and Nayuta, the daughter of the Pandora’s captain, is also excited to see the creatures brought back from the Forbidden Continent. She happens to meet a mysterious young boy on Eden Island. Sen warns Nayuta “You don’t know the real reason the “Forbidden Continent” is forbidden”…what does Sen really mean!?

A rootless mercenary meets the Crown Prince of a certain country. This meeting just might be a ray of light in the darkness for the supernatural war that will soon begin to tear the land apart.

The story takes place a year after the ending of Worst, when Sajima Yousuke and Miyamoto Sanmon are seniors at Suzuran High School.

As of May 2018, the last work in Takahashi Hiroshi's Crows x Worst universe by the original author himself. A two chapter gaiden story about a younger generation of Suzuran's crows, released in 2015.

Protagonist Sakuragi Ryou was in the "A group" in middle school. At least until he got caught up some trouble and developed a reputation as a delinquent. Wanting to live a normal, peaceful life in high school he decides to do a reverse high school debut, aiming to be in the boring, middle-of-the-pack "B group". Above all else he doesn't want to stand out. But then one day he encounters the school idol, Fujimoto Erika, being harassed by delinquents and begrudgingly decides to help her out. She then starts to develop an interest in him, which is going to make his goal of not standing out tough...

Our protagonist, Ichimura Tamito, is a criminal magnet. Ever since he could remember he had attracted criminals from kidnappers kidnapping him when he was just a newborn, to robbers stealing his toys. He is determined to start a new life and make new friends after moving into a new city but at the start of the day he was bombarded by all sorts of crime. After encountering a knife wielding killer in broad daylight he saves a young girl that coincidentally belongs to the same class as he does. But something seems off about this girl and his new class too. It seems like our protagonist's magnetic pull on crime and criminals is getting stronger as he find out that he belongs to a class of criminals and suspects.

Love is the new kid on the block when he runs into the Peach Club, the local gang. Simple and gentle, with an interest in sex toys, Love isn't looking for trouble. Too bad the gang's got plans for him. And so does their leader, Peach.

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?

From JanimeS:

The world of Siesta is set in fantasy Europe where there are people called bullet users who were discriminated against badly for reasons unknown to readers as of volume 1.
The discrimination has gotten much weaker due to Grande Corp's efforts to wipe out the decades-old pirate faction with the help of Bulletron, a battle suit designed exclusively for bullet users.

The story begins as the protagonist Dia Canto tells you a little bit about herself: how she became an orphan, how she met her foster family, and how she is very much in love with her step brother, Loe. However, her affection toward Loe is brutally crushed before it would even bear fruit and she goes out to vent her sadness. This is when she encounters Cid Leon, who she would ultimately be paid to "protect".

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?! 

Manhwa you may like:
+ This is another ambitious work of Sung San Young, The Gamer
+ Tower of God
+ The God of High School

Superpowers are now common among the world's population. The manifestation of powers is known as Girls' Witch Syndrome, and the origin of the sudden large scale bestowal of extraordinary abilities to children is an entity named the Mother Witch. Ayumu Takenami carries the title of Brave Star as the top ranking CARD member.

CARD is an organisation formed from the children and girls that have superpowers. After he dispatches armed kidnappers with his bare fists somewhere in the Middle East, Ayumu drops everything to go see his crush in Japan. Yuki Saimiya is an average 17-year-old high school girl with insignificant powers but wishes she could be more like the rumoured Brave Star.

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.

The young Erwin Smith is a rising star in the Survey Corps, humanity's only hope of defeating the man-eating monsters known as Titans. Ruthless and dispassionate, Erwin’s mind is devoted to strategies and intrigue. But beneath Erwin’s feet is another world, the Underground, where humans are born and die surrounded by the garbage the Capital throws away. Here, the criminal Levi survives on his wits and agility. But when these two ambitious men cross paths, who will prove himself stronger?
The origin story of Levi and Erwin.

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.

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