The story set in the contemporary South Korea. Some 30 years ago, unidentified creatures appeared out of nowhere and have attacked people. They have caused massive destruction wherever they go. The monsters are called "Trouble"s, and get the world have fallen into chaos. Along with the first appearance of the "Trouble"s, some number of humans were born with or acquired supernatural abilities. These mutants called "Trace"s are the only ones who can fight the "Trouble"s. The "Trace" are also considered freaks and generally shunned by the community because some of them misused the powers for their own interest. The plot revolves around two main characters. Sa Ghang-Gwon, a high school student born as a "Trace" who attempts to hide his ability. The other is Kim Yun-Sung, who acquired his "Trace" abilities during his early 30's. Webtoon from Daum

18 years ago, a powerful monument was discovered on a mysterious island. The momument contained data only certain people could extract – who became students of the island’s school. By being able to extract the data, the students are able to summon a creature that they fight with. Of these people, Satou Taketora is your typical lazy kid who doesn’t do anything, hence he’s ranked dead last. But one day, he’s dragged into a battle with his old childhood friend, and to everyone’s surprise… his summon is more than meets the eye…

From ShoujoMagic:

High-school freshmen and twins, Nae and Moe, and Ken and Takeshi, enjoy their lives as students and close friends. Until Moe suddenly dies in a traffic accident... and her corpse disappears? Between the vanishing corpse and a pharmaceutical corporation, her three remaining friends are struck with the reality that something is amiss in their world...

The genius robotics professor, Dr. Komyoji has created Jiro (who has the ability to transform into Kikaider) – a humanoid robot tasked with the protection of Dr. Komyoji’s son, Masaru, and daughter, Mitsuko. Gifted with a conscience circuit, which has the power to simulate real emotions that helps to distinguish between “right and wrong”, Jiro must protect Mitsuko and Masaru from the evil Dr. Gil who wants Jiro to join his army and aid in his goal of world domination.

The Komugi family cake shop, Sugar & Spice, has fallen on hard times. What was once a sprawling business, built up by Nanoha's grandfather, fell apart as soon as her father succeeded the business.

Suddenly, aliens invade. Their scanner identifies a cake as a potent superweapon able to change the course of the Galactic War. So the private leading the invasion decides to investigate further by baking cake with Nanoha.

Follow the adventure of Caisar, the chef on the spaceship of Manado, a group of sexy monster hunters!

Yaegaki Meguru's next door neighbor is unique, to say the least. They are the Kusanagi ninja lineage, and their son, Kanata, has been her classmate and friend since their younger years. Kanata would always get into trouble or be late to class due to his ninja upbringings. Every morning, Meguru would have to pull him away from his training with his father. Most days, he's late to class anyway. In the past, they both vowed to never hide secrets from each other, yet Kanata would not reveal the "true purpose of a ninja." Meguru understood the reason behind Kanata's secrecy regarding his ninja background when a powerful force is released inside their own school. Then, Kanata will reveal his true potential as a ninja.

‘Salaryman from Hell’ is the first in a collection of Ebisu’s stories entitled “The Man Who Saw Hell.” It’s about the day in the life of a normal Japanese salaryman. For the uninitiated, salarymen are an iconic figure in modern Japan, taking the role of everyman. Ebisu uses this generic salaryman figure in most of his stories.

Mayama Haruki and Himemiya Tsukiko have been childhood friends and neighbors for as long as they can remember, but after a girls-only meeting in fourth grade, Himemiya distanced herself from Mayama. Now in their 2nd year of middle school, Mayama has become an ero-freak who specializes in harassing Himemiya. Determined to unravel the greatest secret of girls, what happens on "that day", Mayama follows Himemiya and uncovers.

The main character Totoki is an ordinary high-school student who leads a mundane school life.
One day, a mysterious, primitive girl, Cherry appears before Totoki! Whatever Cherry does is a mammoth class! Because of that, Totoki is being thrown around mercilessly! Is Totoki's normal life gradually changing?!

Ichigo is out on a date with her crush when suddenly she's involved in an odd incident in which her DNA is merged with the DNA of an almost extinct wildcat. When four other girls' DNA is merged with the DNA of four other almost extinct animals, it's apparent that they're part of a much bigger plan. Ichigo and her friends have been chosen to become a part of a secret project called the "Mew Project." Their mission: To protect the planet from aliens who are using the planet's animals to attack humans.

Chica is packed away to sleep in an escape pod in order to avoid a deadly asteroid collision on Earth. When she wakes up, however, she finds herself in the distant future, but still on Earth. Earth is now filled with strange creatures, like flying fish. She's being cared for in a dome by an android guardian named Roy and a maid android called Silvia. She also encounters a mysterious, friendly man with cat ears, named Oboro. All the future beings are fascinated with her, seeing as she's an 'original' human, but sometimes they forget about the limitations of human lifeforms. Will Chica be able to find a place in this strange new world?

Amidst the chaos of World War II, two Japanese soldiers hear of Zephyrus, an utterly captivating woman rumored to exist on an island in the South Pacific. The tales of this bold enchantress seducing men to their dooms are both chilling and fascinating. Over twenty years pass, and Zephyrus resurfaces in Japan, seemingly unchanged, to wield her mysterious power over men once more.

The one man immune to Zephyrus' charms is simple drunkard, Gohonmatsu Seki, son of one of the wartime soldiers. Employed to spy on Zephyrus, what will Gohonmatsu uncover about her ultimate plot to create international discord and consume the world of men? What brought this woman to conspire for decades against patriarchal society-against an entire gender-and can anything be done to stop her plans?

The story set in the contemporary South Korea. Some 30 years ago, unidentified creatures appeared out of nowhere and have attacked people. They have caused massive destruction wherever they go. The monsters are called "Trouble", and get the world have fallen into chaos. Along with the first appearance of the "Troubles", some number of humans were born with or acquired supernatural abilities. These mutants called "Trace" are the only ones who can fight off the "Trouble". The "Trace" are also considered freaks and generally shunned by the community because some of them misused the powers for their own interest. TRACE Season 1.5 - Communicator Webtoon from Daum

Mari Kurusu has had a crush on Kuro Rouzen (the weird guy in her class) for quite a while and when he eats her love letter she thinks it means rejection. Later she finds out his secret, that he is part of a top-secret organization that protects the humans of Earth and he brings her back to the organization to erase her memories. But for some reason, the organization choose's not to erase her memory...

The manga is separated into 3 story arcs with close to none relation with each other's characters.
Volume 01-13: Video Girl Ai
Volume 14-15a: Video Girl Len
Volume 15b: Video Girl - Complete Story (about Video Girl Haruno)

Video Girl Ai [From Viz]:

High-school student Yota Moteuchi is so unpopular that his classmates have given him the nickname "Dateless." So it's no surprise when the love of his life, Moemi, is not interested in Yota but instead is in love with Yota's best friend, Takashi. Yota turns to a video rental shop for comfort, but little did he suspect that the shop was magical and that the cute girl on his rented tape would pop out of the television and try to fix his ruined love life!

"To Hiiragi Kouichi-kun. I'll be waiting for you after school behind the school gym. Sakuragi Umeko." These were the words written in the first love letter Hiiragi ever received. But when he meets Sakuragi, she tells him that she wants to take him to the planet R'lyeh!?! Disappointed that the love letter from the cute girl came from a nutcase, Hiiragi returns home, only to find that Sakuragai won't give up so easily. Not only that, she may have been telling the truth afterall! But then again, Hiiragi isn't such a normal guy, either...

Our hero Vash the Stampede disappeared for two years after blasting a crater onto the moon above the desert planet he saved from annihilation. But with good people and bad alike trying to track him down, he won't stay lost for long! Count on more crazy gunslinger action, new dastardly villains...and a new outfit, to boot! Nightow changed publishers to Shonen Gahosha and the series continued to be serialized in Young King Ours magazine. Due to the original publisher retaining the name Trigun, Nightow had to change the title to Trigun MAXIMUM, which isn't a sequel; just a new name for the rest of the same series.

Yuria is a humanoid dutch wife (love doll), a female android designed with the sole purpose of being the sex slave of her master. But she has one flaw: she doesn't want to be a dutch wife. After escaping from her creator, she meets Kubo Shunsuke, who gives her a place to stay. Hilarity is bound to ensue as she battles her programming, which draws her towards him and pretty much any other man she comes across.

Aoshima Hitoshi is a second-year student in high school, who wishes he had a girlfriend. One day he wakes up for an unknown reason 10 years in the future, and he is married to the prettiest girl in school, Wagatsuma Ai! How has their relationship grown from mere acquaintances to husband and wife!?