From Yen Press:

Rescued from the darkness by Xeno, a mysterious swordsman, Claudia the Rose Witch is the foundation of the Crimson-Shell, a special division of the Red Rose—an organization aiming to capture the results of one mad scientist’s experiments, the deadly Black Roses. But when Xeno’s loyalties are called into question, will Claudia be strong enough to believe in her dearest friend? And what is the color of the rose blooming in Xeno’s heart—a deep, passionate crimson…or a traitorous jet-black?

Carl van Hellsing has vowed to hunt down the vampire Elliot for eternity. But, that's exactly what Elliot wants. Implicit shounen-ai.

The people of Earth live in a society where vampires aren’t just real but dangerous. Although humanity has been able to keep them under control and even take the night away as the vampire’s natural habitat, some of them have adapted. Hesperides, a relatively new breed of vampires, have adapted over hundreds of years in order to be able to go outside during dusk when the sunlight is at its weakest and feast on humans. Aburaya Shiro, a high school kid, lives in a town where there has not been a vampire attack in years, but adults keep warning them of going outside at dusk. Shiro and his classmates take this warning lightly and head out at dusk only to find out one of their classmates who they thought they knew well turnz out to be a Hesperides. With all his classmates violently murdered, the only way Shiro was able to survive was with the help of a different classmate, Ichijoji Eruka, who doesn’t seem to be human herself.

Nemu is back home.
What's gonna happen with Junichi's life after this reunion with his sister?
"Da Capo" in Italian means "From the beginning"... then will we see the end to this romance?

Taking place approximately 50 years after the original D.C. - Da Capo series, the story revolves around Sakurai Yoshiyuki and Otome & Yume, the two granddaughters of the original D.C. - Da Capo protagonists Junichi and Nemu.

This is actually the second manga based on Da Capo II in active serialization. The other manga, running in Kadokawa’s Comptiq magazine, is considered to be the “canon” adaptation of the story (i.e. it’s based directly on the game). As the title “Imaginary Future” suggests, this manga proposes an alternate deviation from the game’s premise, where fan-favourite Shirakawa Nanaka (speculated to be a descendant of the famous Shirakawa Kotori) is the story’s main heroine.

Wizards are never a single entity. That is, they are composed of a partnership of the "holder" and "caretaker" of the stone.

Celeste is the "holder" of the stone, and she's in a hurry to become an independent wizard. But her partner, Chris, is not the easiest person to work with...

What lies below Tokyo's subway system is more frightening than you could have ever imagined...in its subways there exists a boundary between this world and the next--the land of the dead, and the mysterious young man Seiya is its guide. In this collection of bone-chilling shorts, follow the twisted tales of death and hauntings that inhabit this horrifying underworld, where innocent youth fall victim to the ghosts who inhabit Tokyo's underground.

Note - this was originally a GlobalManga, and not of Japanese origin. However, all 3 volumes have since been issued in Japan.

Manga adaptation of Dante Alighieri's classic work "The Divine Comedy".

New cop Asuku finds himself assigned to a special unit of inhuman police agents, tracking down similarly inhuman targets. Only time will tell which will kill Asuku first, a rogue criminal... or his partner.

Summary from Iskultrip Scans: Story 1 (Phantom Lim): Lim and Iota live in a robot country. Lim, who is in love. Iota, whom she loves. The kind robotic maids. Lim has always thought her sunshine-filled days would go on forever, but... what is this promise Iota made with her in the past and the secret that he's keeping from her?

Remember that plague you learned about in history class? Well, it's back, ready to infect hordes of people! Follow Nagasawa, a melodramatic student caught in the middle of this horrid epidemic, with absolutely no idea what's going on, trying to get through life with infected people all about. Can you say creepy?

From Awakened Memories: The new school Lilia has just transferred to has a lot of people with suspicious abilities. There are vampires with fangs and the snow woman's son. And then it turns out that Lilia herself is a demon who sucks the life out of men by kissing them!?

From GOoC:
Data is a kind of Magical Boy series manga by Tachibana Kaimu. The two main characters, Sakura and Yuki, are on quests to gather stones with magical powers. In doing so they are also hoping to uncover the mystery as to why they both seem to have lost their memory. A lot of new characters who are also "hosts" for the stones join in the fun as the story progresses.

From Yen Press:
Ten years ago, the mysterious Hell's Gate suddenly materialized in the middle of Tokyo, and the stars of the night sky were obscured in darkness. In their place, new stars emerged, each corresponding to an individual endowed with supernatural abilities. Devoid of emotion and conscience, these powerful killers have come to be known as Contractors.
But most people know nothing of the Contractors in their midst, and high-schooler Kana Shinoh is no exception. Still struggling to pick up the pieces after her father's death last year, Kana has never troubled herself with the rumors about Hell's Gate. That is, until she spots her father in the street one day. Determined to prove her father is still alive, Kana begins her search, but her mission is attracting some rather dangerous attention. Fortunately, she is rescued from the clutches of death by Hei, the most wanted Contractor in Tokyo. Though he is unsympathetic to her situation, Hei agrees to protect her as she searches for her father. But just how much should she trust the Contractor known as the Black Reaper?

Year XXXX, The Age of Chaos, a dictator meets a vampire who has awaken from 300 years of slumber and is hungry for some tasty blood.

Ninomae Iko, has lived in a house of only her dad and brothers, who all practice kendo. Looking to become a little more girly, she transferred to an all girls' school. Here, rumor has it, a magical cup filled with red wine will grant any wish if your blood is dropped into it.

Note: Plenty of pantsu moments.

Monsters descended upon the humans all of a sudden, monsters that can't be detected by most, unless they have a strong sense. An invisible predator, it feasts on humans to grow in strength and powers. 4 Death Gods are chosen to destroy these monsters and to seal the "sink" hiding the monsters fast.

Fudou Jun is a highschool teacher and takes a trip with a group of students. While there, a group of martial artists staying nearby take a strange interest in the girls.
These men are actually demons and after changing into their true form break into the cabin to rape the girls. One gets Jun and violates her.
She feels her soul being torn apart and transforms into Devilman Lady. With newfound powers and strength she kills all the demons and protects the girls from any further harm.
What are these demons and why did she turn into a hybrid of one? What does this mean for her and for the rest of humanity?

In the midst of a terrorist attack that kills all his classmates,Tohru Kuroe knows the chances of seeing yet another woman die makes Tohru pick up an abandoned gun - The beast awakens; taking over. When Tohru comes to his senses, he finds he is now a killer. Finding out he was genetically engineered to be a killer, his codename is D-17, Tohru continues his 'normal' life amidst challengers threatening his life and those around him.

A collection of three stories of love and the supernatural:

I. Desert Storm. It's four years after the Chechnya revolt against Russian rule. Eimi finds a mysterious boy who speaks Japanese, just like her father. Because he can't recall who he is she calls him "Yuuji." And Yuuji's strange powers tell Eimi her first crush is still alive...
*Related to Silent Eye

II. The Garden of Wild Roses. Garden designer Shindo Chika is surrounded by mystery. One by one people she knows are injured or suddenly die. The only clue she has is a boy with a scarred face--who she fears is a shinigami.
*Related to Towa kamo shirenai

III. Sunset Encounter. Ryuugi dreams each year on his birthday of a girl named Fumika who he loved as a boy name Sou, and another boy named Keishi, who kills him. But when the people from his dreams keep appearing and he starts dreaming events that take place while he dreams, then he begins to wonder what exactly is happening.