Adachi, Mitsuru

The story is set in a place very similar in appearance to Earth in the Edo period. However, Adachi (the mangaka) regularly reminds the reader all throughout the series that the setting is another planet in the distant future which just happens to look like Earth.

After the death of his mother, Shichimi sets out to join his step-brothers and -sister who live together in Karakuri Tenement, a place provided by the father they have never met. He finds out that each of them had different mothers (all of whom have died), but were fathered by the same man. Not long after Shichimi's arrival, the siblings decide to journey to visit the graves of each of their mothers. On this journey, they encounter many dangers.

(Source: Wikipedia)

Nijiiro Tougarashi

虹色とうがらし

Obata, Takeshi

Sendo, Susumu

In a world where djinn rule and humans are enslaved, Toto and Loukir break the seals of the century-old prison of the "gentle genie," Rampou, in order to try and save their country...

(Source: Deja-vu)

Arabian Lamp Lamp

魔神冒険譚〈アラビアン〉ランプ・ランプ

Ishinomori, Shoutarou

Chobin is a funny creature that falls on the ground after the capture of his home planet by the tyrannical forces of Brunga, a demonic figure in a dark coat with bat-like wings.

(Source: MU)

Hoshi no ko Chobin

星の子チョビン

Uno, Hiroshi

At the end of 19th Century, Captain Drake, the pirate who traveled all over the world died. Rumor has it that he hide his treasure that is worth thousand millions pounds away from people. The map to this treasure is being torn into 2 parts. One part of it is owned by the military, lead by Colonel Visconti. The another part is owned by Drake's son. 

That young boy's name is Captain Kid, and with his Black Lightening sword and Kid's cunning crews the journey to find Captain Drake's hidden treasure begins.

Captain Kid

キャプテンキッド

Takeuchi, Naoko

"The Pretty Guardian in a Sailor Suit! Sailor Venus has arrived!"

Thirteen-year-old Minako Aino is an active tomboy who loves idols and video games, and is a popular member of Shiba Koen Junior High School's volleyball team. One day during her PE class, Minako accidentally stumbles upon a white cat, who later sidetracks her from talking to her crush. At home, Minako wonders if she is beautiful, and hearing this, the cat introduces himself as Artemis and gives her a compact mirror that shows Minako more than just her beauty.

Before she can fully take in the cat's words, Minako receives a special pen that can transform her into the masked champion of justice, Sailor V! As her carefree love-seeking days begin to include adventures against the energy-seeking Dark Agency, Minako will learn to embrace the full extent of her destiny.

[Written by MAL Rewrite]

Code Name wa Sailor V

Codename: Sailor V

コードネームはセーラーV

Oukami, Mineko

Meet Rune, Rath and Thats—three warriors with dragon blood running through their veins. They've sworn allegiance to the Dragon Lord Lykouleon, and whenever evil shows up in the kingdom, it's up to the three Dragon Knights to save the day. The mighty trio are on their way home for rest and feasting when an incompetent witch and a demon rudely interrupt them. It's no fun fighting bad guys on an empty stomach! Oh well, it's all in a day's work when you're the most famous warriors in the land...

(Source: Tokyopop)

Dragon Kishidan

Dragon Knights

ドラゴン騎士団

Tezuka, Osamu

Collection of various short stories. 

(Source: M-U)

Tiger Books

タイガーブックス

Nagai, Go

Soft-hearted Akira Fudou has always been somewhat of a pushover. When he reunites with his childhood friend, Ryou Asuka, in a fateful encounter, Ryou reveals to him the terrifying reality of his father's research: demons exist and are planning to claim possession of the earth once again.

Eager to help his friend save humanity, Akira agrees to attend Black Sabbath, a party filled with depravity and corruption, to attempt to merge with a demon. A near-death encounter causes him to unify with Amon, a demon feared amongst even his own kind. Together they form Devilman, a combination of Amon's strength and Akira's pure heart.

After uniting with Amon, Akira begins to fight against the demons with his newfound power, desperate to stop the downfall of all human civilization.

[Written by MAL Rewrite]

Devilman

デビルマン

Watanabe, Michiaki

Pandora's Box led a cursed existence. Through the curiosity of a woman, evil was unleashed and very nearly covered the world in darkness. Miraculously, humanity managed to seal Maou Kestra back into the box, but only with immense sacrifices. Even without their lord, the demons are still a formidable force that has only grown stronger with time, locked in the abandoned capital of the North, Hameln. Fifteen years have passed since that fateful battle...

Meet Hamel, a travelling minstrel who is so self-centered that he'd sooner cook his guardian crow (and family friend), Oboe, than go hungry for even a minute. Welcome to the world of music and hilarious insanity that is the Violinist of Hameln. Watch as Hamel takes cheap shots at his opponents and bashes pigeons with his giant violin and turns them into dinner.

How WILL the world be saved from Maou Kestra with a hero such as this?

(Source: MU)

Hameln no Violin-hiki

ハーメルンのバイオリン弾き

Manabe, Jouji

It`s face-to-face confrontation when Kahm stares down her father and refuses to end her relationship with Tetsuya. In retaliation, her father sends a punitive fleet to Earth -- with orders not only to crush the rebellion but to annihilate the entire solar system!

(Source: Amazon)

Outlanders

アウトランダーズ

After the cruel lord Daigo Kagemitsu sells his newborn son's body parts to 48 demons in exchange for power, he casts what remains down a river and quickly forgets about his son, soon establishing a mighty kingdom. Little does Daigo know that his child survives, possessing advanced spiritual senses that allow him to navigate the world without eyes, ears, limbs, or even a voice.

A brilliant doctor rescues the son and raises him as his own, naming him Hyakkimaru and fitting him with advanced prosthetics that make it possible for him to move and fight. However, tragedy strikes when Hyakkimaru turns out to be a beacon that brings demons into the doctor's home, and the doctor eventually has to send Hyakkimaru out into the world.

Amid his travels, Hyakkimaru learns that slaying demons allow him to recover his missing parts and seeks to kill enough to make himself whole. He soon encounters Dororo—a boy claiming to be the world's greatest thief—who joins Hyakkimaru against his will in hopes of one day obtaining his sword. Together, the duo travels through a countryside infested with both demons and brutal men, who might prove to be worse.

[Written by MAL Rewrite]

Dororo

どろろ

Kanzaka, Hajime

Araizumi, Rui

Young sorceress Lina Inverse and her dim-witted sidekick Gourry Gabriev travel through a somewhat medieval setting, doing good and fighting evil. Well, by "doing good and fighting evil" I mean "stealing from corrupt rich people and blowing things up".

The stories in this volume are occasional tie-ins to the novels and short stories. 

(Source: MU)

12 Manga Like One Piece: Vivi no Bouken