From Hyper Parfait:

Kuchiki, a flutist, was plagued by nightmares every night that forced her to seek the help of counselor Matsuzaki. Ishikura, a police inspector, unexpectedly discovered a headless mummified body in an empty apartment and is now on the case. When Kuchiki regains her lost memories, the curtains also opens to a tragedy!

Asahi and her friend Yamato went together to an exclusive event as test players for a new game from the cellphone-game company "Sky Nova." The test players were a diverse lot of all ages, from ordinary teens like Asahi to popular idols. The company took all of them on a cruise to explain the rules of this island-based, treasure-hunting survival game. Suddenly, during the presentation, all of the participants lost consciousness. They woke up on an actual island wearing a strange watch with the words "Game Start." Now they are all stuck in this survival game, which has become all too real and deadly!

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.

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".

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?

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?

DeroDero is the story of a juvenile delinquent, Hino Mimio, who happens to also be a psychic. His ability to communicate with the spiritual world as well as his demeanors caused him to constantly interact with supernatural beings -- usually ending up with Mimio beating the crap out of the monster or spirit.

Du Ming, young anesthetist in a big Chinese hospital, is haunted by the memory of Zhang Qian: a young lady coming from the same school as him , who bewitched him by the sulphurous beauty and the aura of strangeness she emits. After graduating, Du Ming stayed in touch with Zhang Qian, who writes him. Now a terrible piece of news arises: the young lady is said to have committed suicide. From Manga-News.

The Vampire Bund, a peaceful island nation of vampires off the coast of Tokyo, ruled by Princess Mina Tepes, has seen its share of conflict and turmoil. Yet there are times of relative tranquility when the Bund is a popular tourist destination.
When two teenage tourists visit the Bund and are unexpectedly turned into vampires, they appeal to Mina and her loyal lycanthrope bodyguard, Akira, for help. Their only hope is to find a cure to reverse their vampirism within forty eight hours, or they will be stuck as vampires forever.
Unfortunately for them, their race against time turns into a game of cat and mouse that takes them across the entire Bund in pursuit of the one person who holds the key to their salvation.

A young man reads the suicide note from his deceased sister...

Some more stuff to add to the Devilman mythos. This is Kinutani Yuu's second story about Go Nagai´s work.

From Aerandria Scans:

It starts with poisonous herbs under the cradle. Then under the sheets. And inside the clothes. Even mixed in the milk that they feed the newborn. This way the child gradually gets used to poisons and becomes the perfect assassination tool - the “Poison Princess” whose every kiss, tear, and even touch bring death. Her only chance of survival is to fulfill her duty as an assassin and find a way to live on in the enemy land she is sent to…if her heart is strong enough.

From Yen Press:

A Japanese cell phone game called Rabbit Doubt has gone viral in Tokyo. In it, players are rabbits who must do everything in their power to uncover the wolf in rabbit’s clothing before it kills them off. The wolf, a randomly selected player, must use his wiles to create mistrust among the rabbits and knock his adversaries off one by one. When five fans of this game decide to meet offline for fun, the last thing they expect is to lose consciousness and wake up trapped in an abandoned building with a corpse strung up in front of them, a mysterious barcode tattooed on each of their bodies. Will the virtual friends be able to pull it together in the real world and figure out what’s going on in time to avoid ending up the wolf’s dinner?

In the horror of witnessing so many classmates perish before his eyes in a violent train wreck, Teru discovers two survivors in the tunnel: Ako and Nobuo. But salvation from this bloody carnage is far from their grasp. As they try to dig out from the wreck in order to come up with a plan to stay alive, the lack of light and food, combined with the stench of death and decay, will lead one member of the group down a dark and demented path. And with sudden, violent earthquakes shaking the tunnel, escaping to the outside world may lead them to an even greater danger.

Won the 21st Kodansha Manga Award for general manga in 1997.

Japan is a brilliant model of Asian success and obligation. But how would this country manage a large-scale sanitary crisis? What would happen in Shinjuku, one of Tokyo's biggest districts, if a man exploded in the street during broad daylight? How would the political and sanitation authorities manage such a crisis? Please consider this question as long as you can--because it's already too late for professors Onodera and Sekiguchi! Is an emerging virus slowly spreading itself into the arteries of the Japanese capital?

The story involves human mutations called "Diclonius", who grow horns on their heads and possess telekinetic powers, in the form of invisible "arms" called vectors.
The tendency for violence among Diclonii varies among characters. Certain scientists contain them in a Facility in cells, where they are subject to inhumane experiments to test their abilities or where they await execution for being too dangerous.
An infectious virus is also associated with the mutation. This virus is spread through non-lethal contact with the vectors of a diclonius.
The main non-mutant character in the story is Kouta, who ends up becoming increasingly involved with these dicloniuses, as they seek refuge from the scientists.
The main diclonius character is Lucy/Nyuu, a killer whose alter ego is a hapless and very cute child whose vocabulary and intelligence are quite limited.

There was a fire. Kousei lost his mother, his father and his precious little sister, Sanae. One month later he woke up to find himself in a hospital and was moved to pediatrics where he could share a room with other boys his age.

Professor Kimishiro is loved and respected by his students, but disliked by faculty and administration. He's pushed from his classroom by university politics and takes a team to the jungles of the Amazon in search of new medicines and perhaps a chance to gain back his reputation amongst those with influence back home. Instead of cures, his team stumbles upon a lost temple in the jungle, a place the village guides claim to be 'The House of the God of the Black Death'. What are the temple's secrets, and can any man, let alone a mere boy, survive the plague of an angry God?

Five intriguing creepy oneshots by five different authors. Fallen women: High school girls are all about their looks to get the boy they like. What do they love more their must important person or their own beauty? Transient Future*: The main character's day keeps repeating over and over every day. Each day our Tsukamoto's beloved Yoshi-kun dies. How can she prevent this from happening?