For four decades, Golgo 13 has been the world's greatest assassin for hire. Sometimes to settle a private score, and sometimes to change history!

His real name and nationality are unknown but his legend is everywhere. Golgo 13 never fails a job and never sees his clients again. Unless they try to betray him.

Note: Won the 21st Shogakukan Manga Award for general manga in 1976.
Is the bestselling seinen manga as of 2016 with 200 million volumes sold.

When childhood innocence gives way to a blinding thirst for revenge, is it worth the price of one's humanity?

Tetsunosuke and Tatsunosuke are the sons of a diplomat who sought to bring peace and prosperity to Japan during the early Meiji Restoration. But when their parents are murdered before their very eyes, Tetsu seeks to join the Shinsengumi, the unofficial police who are capable of the same brutality as his parents' murderers. Wading through a sea of espionage, deception and bloodshed, the young boy must choose: should he take a step on the path to becoming a demon...or give up his rage and transform into the ultimate Peacemaker?

From Easy Going Scans:
The story of a boy and girl whose lives were one day entwined by red string. Literally.

From DragonVoice: This is naturally a shounen manga and deals with the orphaned boy Hyouta who's in a group of traveling entertainers and one day he encounters a fine noble woman named Tokiwa who requests the group to perform at her home. But her intentions are not what they seem to be... Read the rest for yourself ^^ The first chapter will probably remind you guys of the story of "The Prince and the Pauper".

From Easy Going Scans:

In the near future, Mother Nature has decided to fight back against all human encroachment.

The world has entered your standard apocalyptic scenario that you can find in many forms of fiction, but it's right in the middle of the apocalypse actually happening, rather than in the aftermath. Vines and foliage entangle cities, as large wooden mech-like creatures called Arethusa (named after one of the mythical Greek Hesperides that tended the gardens in a remote corner of the world) rampage through cities.

Souma Shin, a punk kid out of Japan, went to visit his brother Ken, but all hell breaks loose as Shin finds a group of small kids being used for military purposes. He tries to save them in the confusion created by an Arethusa invading the compound...

From: Easy Going Scans

Everyone in his Yakuza gang looked up to him.

He was the boss's favorite pupil, but then in a single night, after he had won so many territorial fights for his gang, he lost everything! Why?

Takahara Jin is a former delinquent in a biker gang. Every day from the day of his entrance ceremony in high school various problems occur that can make him be expelled but from these problems, the power of his arm is noticed and in exchange for not being expelled he must join the baseball club. This series follows Jin as he looks away from his past and gives baseball his all.

Minato is a total loser. He's failed to make it into college twice, he's unpopular with women, and he's unemployed. He seems like the classic-useless-shounen-harem-male-lead...
In truth, however he's actually an Ashikabi--one of a mysterious set of "masters" in an awesome battle royale between hordes of cute girls called "Sekirei."
Since this is an ecchi manga, with their attacks they often happen to... you guessed it--ripping each others' clothes off! Looks like his luck's taken a turn for the better.

From asdf scans:
In near future, mankind has been defeated by the viral parasites named "Gastrea." They have been exiled into a small territory and live in despair, side by side with terror. In this world trapped in darkness Rentaro, a boy living near Tokyo and a member of the "Civil Security"—an organization specializing in fighting against the Gastrea—is used to accomplishing dangerous tasks. His partner is Enju, a precocious young girl. They fight using their peculiar powers until one day, they receive a special assignment from the government. This top secret mission is to prevent the destruction of Tokyo. Set in a near future, this thrilling heroic-action story starts now.

Many different anthropomorphic predator and prey species are intermingling in a fantastical African savanna society! It is a strictly structured society with many rules, such as those governing when and where a predator is allowed to hunt their prey.

One lion, Leon, does not quite fit into the role nature has chosen for him. He doesn't grow his mane out, and, despite his physical strength, he shows no real interest in establishing territory and acquiring a harem of lionesses. But the most abnormal quirk of all is that Leon is a vegetarian lion!

His tiger companion (who has a bit of a crush on him), is firmly of the opinion that herbivores exist to be eaten, but she manages to mostly put up with his vegetarianism. One day, the two of them rescue a frightened gazelle, freshly arrived from the capital. The tiger is less than thrilled to have a pretty female food-animal hanging around with them, but the jackals who are tracking the gazelle seem to have some kind of business with Leon as well...

The resonating Echo of the sword changes the boy's fear into rage.

From Batoto:

Masumasu Academy, an Academic City floating in the Pacific, is home to children with mysterious powers known as "Fiction". "Fiction" grants them enhanced physical prowess, as well as one additional ability. What will happen when a time stopper, Kazuma, meets a cute girl with the ability to move at lightspeed, who knows and is searching for him?

When humanity was threatened 5 years ago, the boy who saved the world was driven to despair and became regarded as the enemy of all of mankind. And now a new crisis approaches humanity. The curtain rises on a gallant drama about a hero falsely charged.

A manga based on the dungeon crawler RPG videogame Etrian Odyssey 2.

An action fantasy manga that takes place in both this life and the next, featuring the boss of the guard tribe that protects the city, Jang Gwang Nam.

The continent of Yggdra is a place where humans, ogres, giants, forest sprites, and many more mythical creatures live. Led by the Holy King, the continent was at peace until one day, a mysterious group called the Black Army appeared and started conquering the land. In response, the Holy King and its troops fought against it, but Holy Capital fell and the Holy King was killed by the mysterious Black King. As the continent was in the glimpse of destruction, hope glimmered as one man, Yuri, the Hero, decided to fight back and formed the Volunteer Army to oppose the Black King and bring peace back to Yggdra.

The story is set in a dystopian near future where the Japan society is experiencing a crime rampage and in which a powerful and secret religious organization, with mysterious goals, is acting as an invisible hand behind the scenes.

The main character is their strongest assassin, lent to them by his fanatic mother when he was a child, and now a ruthless killing machine whose fists and feet cause serious damage to his adversaries, and whose weapon of choice is a special cutting wire with which he grabs and scorches his opponents.

He's a man hunter, whose childhood has been stolen and molded after his tormentors, but when the road of forgiveness is precluded to him what can be left to a man to obtain the redemption?

Takeo finds the answer in the vengeance, and in eradicating that same evil from which he has born.

So this dark and impressive badass guy, after betraying the sect, gets down to business kicking their ass and unleashing his fury against the deadly opponents sent to stop his unparalleled revenge.

In the corner of a certain town, there is a teashop where the master, Tsukasa, obtains and cares for plants from the depths of hell.

SERIES 5: Vento Aureo
Set in 2001 Italy, the story follows Giorno Giovanna, son of DIO, and his dream to rise within the Neapolitan mafia and defeat the boss of Passione, the most powerful and influential gang, in order to become a "Gang-Star" and make the world a better place. With the aid of a capo and his men, as well as his own resolve, Giorno sets out to fulfill his goal of absolving the mafia of its corruption.

Sihoon is a boy who lost his parents and lives with his older sister. This story begins as he meets Mephisto that came to the world to find Faust and makes a deal with Mephisto to supervise the fights between Mephistopheles and Faust.