From Baka-Updates: On one side, we have a guy living a boring and meaningless life meets Touko, a pretty girl, and it turns his life around. They get married, but three months later she tells him she is an alien from a far away planet, and that she must return to her home planet in a few days. Is she making excuses? Is she really an alien? Will he let their marriage end so easily? On the other side we have Honda Haruno, a girl which has absolutely no other recollection other than being "sent" by her superiors to gather information about humanity; as a secret agent she needs to do her best as to learn as much as she can about society without giving away her true nature.... However on her first day of school she meets this boy "Isuzu", who has extensive information about UFOs, invaders from other space & related topics... Haruna not only is surprised to see that her cover has been blown out right from the start, but also she must know how this Isuzu fellow knew about her. Even though they don't realize it; Haruna and Touko are actually neighbors in the Akatoki Hoshi Residence... but, Is this all? Well, you have no way to know exactly how mysterious is the people of the Akatoki Hoshi Residence until you step forward and read it out!

AhMin- Ji-Yoo, who is more like a flower than a flower, a romantic, whom I love AhSoo- Doesn't want to concern himself with others. HweRan- A child who likes to use other people's weaknesses to harm them. Her eyes are always pointing at one place. HaSou- Someone who'll destroy the messed up world. No one not even himself, is not in the world. They, who have seen different worlds, are coming together in one place TO THE EYE OF THE STORM... (from the first few pages of this manhwa)

From MangaHelpers: In 2019, childhood friends Yashio Kaito and Senomiya Akiho are in their last year of high school. Together, they are the only students in the robotics club, which has lost its school funding. Akiho is passionate about robots, and longs to complete building the robot her older sister Misaki began in this same club. Kaito doesn't really care about robots, and is obsessed with video games, specifically "Kill Ballad Online." However, he stays in the robotics club due to his friendship with Akiho. Now, just after Kaito is accused of cheating in his favorite game, Akiho decides to risk her club's existence in exchange for the funding to finally finish her sister's giant robot...

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A military test accidentally sends a modern-day army back in time to feudal Japan. When their actions in the past begin to have an effect on the present, another unit is dispatched to retrieve them. But the commander of the lost unit has other plans. He intends to use his advanced technology to conquer Japan and change his country's destiny. -- {Summary by Mangaupdates.com}

From CPM: The curvaceous cutie Captain Tita pilots the far-future submersible Cha Cha Maru, hunting creatures for the exotic pet market. With only four years’ experience under her belt, can Tita capture an elusive cloud whale and fulfill a vow to her dead father, or is she literally out of her depth on this one?

Utsugi Sou, a high schooler that is very serious about taking out garbage on a daily basis. He lives alone and has a close girl friend. Lately, his garbage has been messed with and redivided by a stranger unknown. And, one day, a transfer student, Tokisaka Koyomi arrives and seems to know him; however, he has no clue. Later, he finds out that the transfer student is from the future. The story begins from here...

from Wikipedia: Justy Kaizard, a police officer who chases down criminal espers; his tactics might be similar to those of a bounty hunter but he is a salary-drawing officer.

Welcome to the future. In tried-and-true sci-fi fashion, the date is given in a time system that we have no reference for, so I can't tell you how far into the future we are beyond saying that it is S.E. 156. Thirty years before our story begins, an ace space pilot by the name of M2 Rimstein was put into an experimental cold sleep until such time as he would be needed. That time is now. He is unfrozen and put in command of the Dance Mania unit of three superb pilots, though two are rookies: Stellasta von Argyll, Malloy Chihaya, and Cloud Neelsen. Accelerated training commences, and new ships and gadgets are brought out so that they will have victory over their enemy. Unfortunately, things go awry fairly soon when M2 is captured and brain-washed by a planet which sends him out to fight for the enemy. Malloy at first refuses to fight his commander, and then does so with the conviction that he can bring him home to the Great Carrier. Bringing him home may be easy, but regaining his mind? from Translated Treasures

A nameless one is searching for his destiny. His fate. But finds nothing but visions of the future and past. What's the point of writing a book if you have no name?

In the year 2162, a tiger cub named Koga was transported to Earth from another dimension. Originally thought to be a normal tiger cub, he was brought up on an endangered animal reserve. Eventually he starts talking, and walking on 2 feet. In 2170, the Earth is attacked by an alien weapon that has the power to destroy countries...Koga is now fully matured and decides to join the Space Force to protect the ones he loves. In 2172, they travel to the alien world to destroy it. facebook.com/galaxytiger

Based on the live action movie. Masaru Aso has gone missing from the public, due to being used as a genetic experiment by Doctor Mochizuki in order to create a perfect lifeform. Aso goes to hide in the forests before he was summoned to save Dr. Mochizuki's son, Hiroshi, from being targeted by monsters from Neo Organism.

From Crunchyroll: Tatsumiyajima is the central island in the middle of a small cluster of islands, in a sleepy backwater of the Japanese isles. Not much happens there, and the island's young people go to school knowing that their lives are likely to remain peaceful and undisturbed. Or so they have been taught... but the truth is different. The fate of mankind is on the line, and Tatsumiyajima is the last line of defense against a hostile and incomprehensible enemy. At the center of it all, fighting for Humanity's continued existence, is the giant robot Fafner, the dragon that guards this final treasure of mankind.

Summary from Vampire Knights: Since youth, Shin had a special ability to foresee dangerous situations. When his sister, Nao, was kidnapped by the people from a research center, Shin finally realized that he was not actually human, but a ‘virtual beast’ created in a genetic experiment. To solve the complicated mysteries revolving about himself and save his sister, Shin and his good friend, Tatsuki, embark on a perilous journey.

The village has been harassed by the ghoul for several decades. Half of the villagers have become the ghoul's food. Deciding enough is enough, the chief of the village gathers warriors to hunt the ghoul. Ciel, along with the hunters, comes to the village for preparations. At night, he heads to the cave deep in the mountain on his own, trying to discover the true nature of the ghoul.

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From Choutomaraseru: An injured soldier on an alien world is rescued/captured by a soldier from the other side of the conflict. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ A soldier from one side of the war is injured and the only survivor out of his troop mates. After he passes out, an enemy picks him up a treats his wounds, forming a bond with each other. After they separate, troop members from town see the soldier but when they reunite, the soldier's enemy/friend ambushes them. Will their friendship stop the fight?

Based on the TV Series of the same name, insects all over the world begin to swarm for unknown reasons, with other animals and plants acting strange as well. To investigate this, Takuya Kai is dispatched with an Earth Academia group. Investigating independently, Takuya finds Guru who reveals that insects are preparing for battle against invaders from another dimension. Offering their aid, the Earth Academia create suits of armor to combat the threat as the Jamahl arrive to Earth to enslave humans. Though they have trouble perfecting the Bio-Machinery, Guru arrives to infuse the armor with the life force of many insects. Once the suits become the B-Commanders, one suit chooses Takuya while the other two bond to Daisaku Katagiri and Rei Hayama. With their newfound power, the B-Fighters fight to drive back Jamahl's forces. (Wikipedia)

Original Series done by Jaiminis Box!

From ilovemanhwa.com: BLOCKBUSTER SCI-FI CHI ACTION FROM THE AUTHOR OF PRIEST! Ton-up kids�� craziest leader Chiwoo prepared a big gang fight to celebrate his 17th birthday, but he finds his father prepared a bigger party as he promised when he left Chiwoo 10 years ago. The party starts with a sudden visit of the agents from the Central Incantation Center of Korea and its enemy, the Unions. Chiwoo is simply shocked by their spectacular Incantation War, but does not realize his power, the Mighty Spirit, the ultimate power these two countries would risk the war for. Which way will this birthday present lead Chiwoo to?

On an alternate Earth in the not too distant future, a monster is found by 2 kids, and shortly after a 3rd friend joins the group. It's a story about the monsters journey through life as he tries to find out who and what he is...and about his true destiny. https://www.facebook.com/grumblemanga?ref=hl

In order to protect the world from the virus “Torikago” that has infected humanity, having fulfilled the condition of living as a normal human being, the young girl, Kiri, conceals the “World’s Memory” within her body. The world loved by the Torikago. The world that continues to reject the Torikago. Over the course of time, while the world erodes the memories of the girl who does not possess a free heart, she proceeds to fall in love…

In the 21st century, aliens have arrived on Earth and live among humans. In sleepy Enohana, the dirt-poor student Chigasaki Mayuko finds herself living together with NieA, a low-caste ("Under Seven") alien. While Mayuko struggles diligently to make ends meet, NieA seems to be totally unconcerned with the consequences of her actions.

From Tokyopop: Daphne in the Brilliant Blue take place in a near future in which the remaining population lives in underwater cities, with waterways as streets. Years ago, while conducting underwater experiments, all contact with the surface was cut off. With the remaining human population now living underwater, The Deep Sea 9 Cities Association represent the last hope of mankind. Ai Mayuzumi is the daughter of the head of the research lab, and is an expert water jet bike driver. When the terrorist group Error, attacks the city, Ai becomes involved with the counter-terrorist group Stelnas, comprised of an all-female team, and led by a girl named Kei, and asks to join them. The group initially resists her efforts to join, but a surprising "gift" that Ai possesses, along with the way she handles herself during a kidnapping attempt, eventually sways the opinion of the members of Stelnas.