Akohito is a simple guy who wants to find a perfect girl, until he met Agate who was a marble turn into a human. He thought his life was turn into a Shōjo manga but he didnt know his life turn into a Shounen manga instead and he will discover that Agate is not just marble girl but is an aion soul weapon.

The mysterious woman, and those who are controlled by her. Don’t be fooled by the devilish hidden grin! The legendary hit author, Lee Jongkyu and the god artist Rigeng’s full length webtoon.

Children who died before their parents change their 'cause of death' into weapons, and kill each other over chance of resurrection....

From HappyScans:
Jubei Yagyu is the head of the Yagyu Clan following the events of Demonic Resurrection and has mostly retired from the world. A group of warriors decide to ask him if he wants to take over a post at their dojo, but Jubei is more interested in watching the Noh of his friend and subordinate Chikuami.
Yagyu Jubei dies is the third in Futaro Yamada's Jubei Trilogy that began with The Yagyu Ninja Scrolls and continued in Makai Tensho/Demonic Resurrection.

http://toptoon.com/ranking/ep_list/YoungGun 

On January 3rd, 2097, a collision with a celestial object basically destroyed human civilization. Seventy years later, human survivors are still living in space, unable to return to their home planet. Some humans, called "Divers" are able to project an avatar to the earth in order to salvage information from earth-based computer networks.

Suzuro is a 14-year-old freelance diver of incredible skill, but only a C-rank due to age restrictions. She works in a salvage ship with her pilot Ginga, who keeps the ship out of flying debris while she's connected to earth, and her assistant Shimugi. It's not only space debris colliding with the ship that could kill Suzuro while diving, there are also dangers waiting on earth that could kill her, just by interacting with her avatar. Suzuro must be certain that the cases she takes are worth the danger!

Hae-Gyeong has a horrible dream in which he meets a terrible group who are killing him saying; "'Boss star' Hae-Deung, the head of Hyeon-Mu! We are here receive your life. Only the universe may know what will be there at the end of this way! Anyhow, you have to die here and now!"
At the offset, it seems that Hae-Gyeong is a very ordinary highschool boy. However, the truth is murkier than even he himself knows... Originally Hae-Gyeong was Hae-Deung, King Hyeon-Mu, in the fantasy world, but his power had been sealed through the veiled enmity caused by his entanglement in the Daegyeolgye causing him to be born into the present world.
Hae-Gyeong is shocked and disbelieving when he hears about this truth from his best friend, Wun-Hak. What is worse, Kin Ju-Jak, suddenly appears and attacks Hae-Gyeong, who has not yet awakened, and he is narrowly rescued by Kin Cheong-Ryong who claims to be his ally.
As he gains a better understanding of his previous life, Hae-Gyeong awakens his powers gradually. How is it going to end?

Hydra is the story of a former cop infiltrating the mob so that he can get his revenge over them for killing his mother & father while leaving his sister in a vegetative state.

Tatakae! Ryouzanpaku Shijou Saikyou no Deshi, relates the story of a peaceful yet weak boy, who one day, after being beaten up really bad by some of his school comrades, decides that being bullied around isn't an option anymore. Seeking revenge on his bullies, the young boy, Shirahama Kenichi, decides to join a fighting dojo. But what he doesn't know is that the dojo he wants to join is actually a place of gathering for those who have mastered different types of fighting styles. Thus begins his journey...
This is the original version that History's Strongest Disciple Kenichi is based on.

From Aerandria Scans:

When she merges her soul with that man, she will become the Goddess of War!

Itsukushima Hinata is a cool high school girl who lived a normal life, but one day, all of a sudden, her life became not so normal anymore. The strange man that suddenly appeared insulted her best friend and enraged her. He's a mysterious man who has a costume like that of someone who just woke up from ancient times. While Hinata is still confused, that man hugs her out of the blue! And then, she transforms...?!

Going on a journey to find his father. Learning about the world and becoming an adult.

Dents is an apocalyptic journey to the year 2111, where more than half of the world’s population has been wiped out by an ancient plague. After a vaccination is developed, there is a massive increase in the birth of identical twins possessing extraordinary powers, known in society as “Dents.” Following an incident at school, Eleanor learns that she herself is a Dent, separated from her twin at birth, and is quickly swept into an underground society of other Dents trying to survive.

From the popular JRPG, produced by Bandai Namco Games, in which "decisions weave the future," comes a comic version. After the incident in "Tales of Xillia," the shell which separated the two worlds, Liese Maxia and Elenpios, deteriorates and the two worlds join to become one, but not the people of the two worlds. Opposition arises between the people of both worlds, especially the Elenpians, leading to the formation of a terrorist group, whose goal is to interfere with the formation of peace between the two worlds, known as the Exodus. The story revolves around Ludger Will Kresnik, a young man who lives in a small apartment in Elenpios with his brother, the elite agent of Clanspia Corp., the giant enterprise of Elenpios. Having failed his exam to enter the same company as his brother, Ludger gets another job as a chef in the train station's cafeteria instead. During his first day of work, he runs into a little girl who wishes to go to the Land of Canaan, the mystic land where all wishes are granted, without knowing that their meeting will unfold the secret of the world and of the strange power inherited within Ludger's family, which ultimately may lead to the destruction of the world. [Ju-da-su]

> Another Story The story of Asch, born Luke fon Fabre to the Duke and Duchess of Kimlasca. This story shows his trust in Van, the loss of his previous way of life, and the other events that led to him joining the Order of Lorelei as "Asch the Bloody" > Another Story 2A story about the life of the Original Ion. It shows the despaired life he lived as a someone who could tell the future, who could foresee everything, including his own demise. It also shows how the God-General Arietta first became a part of the Order of Lorelei, and how she lived her life as the Original Ion's Fon Master Guardian. > Another Story 3The story of Emperor Peony IX and his love with Nephry and his ascent to the throne of Malkuth.> Another Story 4 The story of how Dist and Anise met within the Order of Lorelei and how a they created a dysfunctional friendship that gave both the ability to move forward and show compassion to others.> Another Story 5In the time before the occurances of Tales of the Abyss, Ion resolves himself to do better as a Fon Master. Accompanied by his Fon Master Guardian, Anse and Colonel Jade Curtiss of Malkuth, the unlikely group heads forward to bring peace between Kimlasca and Malkuth.> Part of the Tales series( http://www.batoto.net/search?name=Tales%20of&name_cond=c&artist_name=Bandai%20Namco%20Games&artist_name_cond=c )Main Story:> Tales of the Abyss( http://mangapark.com/search?q=tales-of-the-abyss )

Once upon a time, there existed a giant tree that was the source of mana. A war, however, caused this tree to wither away, and a hero's life was sacrificed in order to take its place. Grieving over the loss, the goddess disappeared unto the heavens. The goddess left the angels with this edict: "You must wake me, for if I should sleep, the world shall be destroyed." The angels bore the Chosen One, who headed towards the tower that reached up unto the heavens. And that marked the beginning of the regeneration of the world.
Colette is the next Chosen of Mana to undertake the Journey of Regeneration in order to regenerate the dying world of Sylvarant. On the Day of Prophecy, Colette receives the oracle at the Martel Temple and thus began her journey to heaven. Together with her two childhood friends Lloyd and Genis, her teacher Raine and the mercenary Kratos hired to protect her, they set off on a journey to regenerate the world.

In the lawless Arang Technical High School, Kim-gu simply hopes to lead his life as a "good student"...

Lead by fate, the two siblings, Senel and Shirley, arrived on the "Legacy", a Relic Ship made by the ancient people of the past. There, they both meet with a band of unlikely allies, learning about the state of the world and discover the path they each must take. This is a tale of destiny about their meeting and the bonds forged between them.

From Abyssal Chronicles:
For a long time now, the Capital Kingdom of Regunum has kept its dominance over the land during the raging wars, and kept the world at peace. There are, however, the recent appearances of humans who held within them great mystical power, the "inousha" (literally translated as "a person with a gift/talent"). The people started fearing these inoushas, and began to detest them. Because of this, the capital of Regunum carry out a movement to seize and capture all inoushas within the land to keep the people at bay. At this time, Ruca, the son of a merchant living in Renugum, discovers that he also holds the same mystical power.

From Boku-Tachi:
The two planets of Inferia and Celestia are bound together by the 'Orbus Barrier' to make Eternia. A young girl, Meredy, from Celestia is sent to Inferia to gain the help from the Inferia summoning elements, 'The Greater Craymels'. Their purpose is to aid the prevention of a crash-course collision of the two worlds, known by the denizens of both worlds as the 'Grand Fall'. Upon landing in Inferia, she joins the entourage of 3 young villagers named Rid, Farah, and Keel in her journey. Based on the game Tales of Eternia by Namco.

Being the child born between Stan and Rutee, two of the 'four heroes' who had saved the world from crisis a few years ago, the young boy, Kyle, has inherited his father’s golden locks, indigo blue eyes and a straight forward characteristic. Day after day, Kyle spent his time longing to become a hero and to experience an adventure of his own, just like his parents. One day, along with Loni, who he had considered to be his brother, Kyle went to the depths of the forest and found a gigantic lens inside an ancient ruin. In his first adventure, Kyle had an encounter with a mysterious girl. Who is the ‘hero’ the girl is searching for? Once again, a famous RPG by Namco is being adapted into a comic!!