From Yen Press:
The air of celebration surrounding fifteen-year-old Oz Vessalius’s coming-of-age ceremony quickly turns to horror when he is condemned for a sin about which he knows nothing. He is thrown into an eternal prison known as the Abyss, from which there is no escape. There, he meets a young girl named Alice, who is not what she seems. Now that the relentless cogs of fate have begun to turn, will they lead only to crushing despair for Oz, or is there some shred of hope for him to grasp on to?

From Wingtip Cafe:
Suzu, an ordinary girl who possess extra-ordinary power to summon demons, was left with a flute, the only keepsake of her disappearing 'Father'. In the flute, dwelt the guardian spirit who responds to her plea in danger.

In the 30th century A.D., in a world in which magic exists, 100 years have passed since the human race won a war against the Devil King. Even though the war caused many sacrifices, slowly but surely civilizations began to rise again.
One day, a virtuous child named Sai Akuto ("Worst Evil") is adopted from the orphanage he's lived in ever since a witch quietly left him at the church as a baby.
Five years later, Akuto passes the test to enter Constantin Magic High School. But after arriving and taking the vocational aptitude test, Akuto receives surprising results:
Examination Numbers: Number 021
Name: Sai Akuto
Future Occupation: The Devil King

After 10 years of training, Yoichi returns home to fight against the Wenkamui, an endless horde of mysterious monsters that threaten the safety of his village. He's not alone in his fight; his best friend Ryuu, drawer of the divine sword Kamui, has also spent this time training to fulfill his destiny. However, a decade is a long time, and upon his return, not everything is as Yoichi expected it would be...

[Written by MAL Rewrite]

From Tokyopop:

Yume innocently uses her magic to help the people she encounters--soccer players, the wrongly incarcerated, or two young lovers wanting to see the moon on a cloudy night. And you can bet that Yume's magic leads to new adventures--and a few mishaps!

The protagonist is sucked in to a weird whirlpool in a river and somehow ends up in a island in another world with native elves that wear leaf clothes, have the knowledge of an new born, and have sex like rabbits. That also have a body as weak as butter.
He decides to become the king of the place and rule with an iron fist and teach the naive elves cruelty, evil and watch as they kill each other.

Young Gabriel Woods is about to discover that his dreams for an adventurous life will lead to something unimaginable. The door to the realm of the oldest race in the universe, GODS, is finally open to humans. From the mysterious dream eaters of hell to the legendary ocean realm of the sirens, the vast mysterious universe lay before him to explore, but Gabe must first prepare. Welcome all to the GRAND ACADEMY of OURANIA for GODS, where you will learn how to truly become a GOD. Is Gabe ready to face the powerful GODS of the new age, or will he regret wishing for more?

A manga anthology based on the DMM Games/Nitroplus browser game Touken Ranbu -ONLINE-.

Blood, war, and betrayal: this is the story of the Scarlet Macaw, leader of an organization devoted to crushing political threats on the Mervellian continent, a part of the Crimson World.However, the Crimson World is becoming darker than ever...http://tapastic.com/episode/81638

In ancient times, all of the demons recorded in the Classic of Mountains and Seas really existed. They absorbed humankind's thoughts to become more powerful. As time passed, people gradually forgot about their existence. The demons that were forgotten were all faced with the fate of disappearing...... there is a family that serves to guard and protect the only demon remaining in the world. As they painted and recorded, they were — the artists of the Classic of Mountains and Seas.Source: http://www.u17.com/comic/81359.html

Jung Yoon-hwan may be an orphan but he was a college student who was focusing hard on his studies, one day he is brought to a mysterious "White room" to fight even when he does not want to. Every time he defeats these monsters he gains psychic power, magic, and items beyond his imaginations....

(Source: Game of Scanlation)

The sky has constellations, and humans have teeth. The earth has hills, and humans have little things.

First year high-school student, Toujo Basara, is now living with two beautiful step-sisters thanks to his eccentric dad. But Mio is actually the new Demon Lord and Maria's her succubus chaimberlain. Throw in a "reversed contract," rival demon tribes, and the ecchi situations mainly brought on by Maria for good measure, and you have a situation where Basara's life will never be the same. This seinen adaptation of the light novel mostly focuses on the said latter ecchi situations that occurs between the three main characters.

On Yumika's 14th summer, a strange encounter gives her a new lease on life..

Siscon. Power-phobia. Son of the great General Luccafort. Son of a general. Wether-crown. Fourth-in-line for succession. The titles, accolades, expectations, respect, and envy for DX Luccafort keeps coming. But all he wanted to do was win Marion's hand.
Landreaall follows DX, his sister Ion, and his bodyguard/brother Rokkou as they leave their home in the countryside and brace themselves to take on whatever their famous last name brings them.

A six chapter mini-series by Miura Kentarou set 100 million years in the future, it's about an epic war between the forces led by Zeus and the nether forces led by the giant Alcyoneus.

From MangaHelpers:

In a strange twist on Arthurian legend, young Art pulls the magical sword Excalibur out of a stone--only to find himself as one of a million Arthurs, fighting to defend the island of Britain from enemies and to earn the rank of the true king. Art is pretty puny, but his childhood friend Ligu (who was also chosen by an Excalibur) tries to keep him from being immediately killed.

Soon Art lives in a castle with knights, which are created beings who serve the kings. From the respect with which he treats the knights, he inspires some to hope he becomes the true king. But is that really achievable by a scrawny crybaby like him? [tethysdust]

In ancient times, all of the demons recorded in the Classic of Mountains and Seas really existed. They absorbed humankind's thoughts to become more powerful. As time passed, people gradually forgot about their existence. The demons that were forgotten were all faced with the fate of disappearing...... there is a family that serves to guard and protect the only demon remaining in the world. As they painted and recorded, they were — the artists of the Classic of Mountains and Seas.

The story of Shiba Occhan follows Uncle Shiba, also known as Shiba Occhan, who becomes a doge after marriage.

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+ Himouto! Umaru-chan

A collection of oneshots based on fairytale/folklore: 1) Cinderella 2) Little Red Riding Hood 3) The Little Mermaid 4) Beauty and the Beast 5) The Bamboo Princess 6) Carmen