This Manga is about an Android that can think and feel like a human being, and even has the ability to choose his Owner...

Orbiting serenely above a long-ago poisoned earth, the last bastion of human civilization is the space colonies. After a terrorist attack, the colonists are forced into exile on the blighted planet below. In the confusion, a young mother is separated from her family and is flung into a bleak, uncertain future... But Sarah will not rest until she finds her children.

It is now the time of the Irregulars. In 1945 the world changed. Physicists opened the gates to hell when the bomb fell. Science collapsed and the world became filled with Irregulars; humans who possessed supernatural talents from birth. 17 year old Eiji Hongo has the power to control the God of Swords, Reppu. Together with this friends, they plan to unite West Dragon city.

The "saber" are immaterial entities that take possession of the body housing to protect our world by exterminating the "frame users" from another dimension. So that when possessed the bodies hosting lose consciousness, Kaon, our heroine, keeps hers. How would she cope with horrific monsters who threaten it now?

Universal Century 0153. During the war between the League Militaire and the Zanscare Empire, Uso Ewin while alone on a reconnaissance mission happens upon the Zanscare Empire's Newtype squad, and finds himself blind-slighted by a Zoloat, and comes under attack by the mysterious Mobile Armor Zong. However he finds himself rescued by an old junk dealer Grey Stoke. The pilot of the Zolat, who was also rescued alongside Uso is revealed to be a young girl named Kamui Gian.

A spin-off of Kyoukai Senjou no Horizon depicting everyday life on Musashi in an easy-going style.

A society where people have forgotten about ethical taboos and enjoy a life with clones, robots, body rental and drugs.

From MangaProject:
This is the story of Alpha Hasseno, an Alpha 7 M2 series robot. Left by her owner, she appears and acts fully human while running a small coffee shop named Cafe Alpha. It is a light-hearted story about the people Alpha comes into contact with behind the backdrop of a futuristic country-side in Japan. As we meet Alpha, she makes a shopping trip to Yokohama.

Note: Won the 2007 Seiun Award for Best Manga.

Jamitov Hymem and Bask Om arrive at the Newtype Research Institute Headquarters located in Indiana of North America. They have come to observe the condition of the newly modified Cyber​​-Newtype, Subject GH-8N-281 known as Rosamia Badam, a girl who was orphaned by the colony drop on Australia during the opening days of the One Year War.

On the outskirts of Neo-Hong Kong lies a mysterious Chinese-style garden. Legend has it that anyone who looks upon the fairy of the garden will die before the night is out.

Five years ago, Douglas Pyke was charged with discovering the true nature of this fairy, but when he accidentally killed a woman in the line of duty, he left the police force forever. Now, a cabbie and sometime private eye, he is asked to find a missing scientist and confront the mysteries of the garden once more.

It's mainly about two different armies battling each other out with their mecha.

From Tokyopop:
In these haunting tales, Dolls-- human-like androids-- have an uncanny way of working themselves into the lives of their masters.
DOLL examines the question of what it means to be truly human.

From Tokyopop:
When Mink rushes to buy the latest CD by her favorite pop star, Illiya, she winds up instead with a software disc from the future that allows her to become whomever she wants. When she and her friends decide to program a Cyber Idol version of herself, all Mink's dreams come true. In fact, she is soon discovered as the next 'It Girl' and causes quite the pop culture sensation. However, Mink cannot reveal her true identity to anyone because using software from the future is a serious crime--and being caught could result in her 'deletion.'

From Tokyopop:
In the year 2068, the Brain Computer, created by humans to be the core of a machine-driven Earth, itself creates Leave, an android that far surpasses the abilities of humans. With mankind now an unnecessary aspect of the Earth ecosystem, Leave, along with her 'father' Fenrir (the human scientist who raised her), destroys humanity and in its stead creates the four 'Mothers' who in turn create an android race modeled on Leave known as the Selenoid.
They divide the world into four parts, each ruled by a Mother, and then further sub-divide the android population into hierarchical levels with the strong at the top and the weak at the bottom. A virtually perfect society ...
And it would have remained perfect if some of the surviving humans hadn't formed a revolutionary group together with some of the lower caste Selenoid with the explicit purpose of overthrowing Leave and delivering the Earth back into the hands of the humans.

Manga adaptation of BlazBlue game.

They arrive in silence and darkness. They descend from the skies. They have a hunger for human flesh. They are everywhere. They are parasites, alien creatures who must invade - and take control of - a human host to survive. And once they have infected their victims, they can assume any deadly form they choose: monsters with giant teeth, winged demons, creatures with blades for hands. But most have chosen to conceal their lethal purpose behind ordinary human faces. So no one knows their secret - except an ordinary high school student. Shinichi is battling for control of his own body against an alien parasite, but can he find a way to warn humanity of the horrors to come?

Won the 1993 Kodansha Manga Award for General Manga and the Seiun Award for Best Comic of the Year in 1996.

Oneshot about pilots killing creatures from sea

Kyoukai Senjou no Horizon 4koma anthology by various artists.Not to be confused with the Horako-san 4koma.Note: Spoilers and in-jokes abound.> Spin-Off of Kyoukai Senjou no Horizon (http://mangapark.com/search?q=kyoukai-senjou-no-horizon )Related:> Kyoukai Senjou no Horako-san( http://mangapark.com/search?q=kyoukai-senjou-no-horako-san )> Kyoukai Senjou no Horako-san - Shucchouban( http://mangapark.com/search?q=kyoukai-senjou-no-horako-san-shucchouban )> Kyoukai Senjou no Horizon - Animedia 4koma( http://mangapark.com/search?q=kyoukai-senjou-no-horizon-animedia-4koma )

From Yen Press:
Kyon is your ordinary high school freshman who has long given up on his childhood dreams of encountering the fantastic and supernatural, or so he thought.
From the very first day of school, his classmate–the beautiful but eccentric Haruhi Suzumiya–makes it very clear that her only desire is to meet aliens, time travelers, and psychics! A chance conversation between the two inspires Haruhi to form the SOS Brigade, a school club created for the sole purpose of getting these supernatural beings together. The initial members consist of the mute bookworm Yuki Nagato, the timid but voluptuous Mikuru Asahina, and the polite and ever-smiling Itsuki Koizumi. By the end of this first volume, Kyon quickly finds out that these seemingly “helpless victims” of Haruhi’s are actually members of secret organizations–both futuristic and alien–keeping watch over Haruhi as she is the pinnacle of some major calamity on the horizon.

Note: A one-shot prototype titled Emeraldas was published in 1975 in Akita Shoten's Monthly Princess.