Nishino Fuuka, an ordinary girl, finds her classmate, who's always dozing off in class, sleeping. She tries to wake him up, and succeeds. He asks her to come with him. She does, and discovers that he's the famous 'high school photographer'. What will happen next?

The first story, Namae no Nai Uma, is a ＭＡＲＳ prequel telling the first meeting between Rei and Tatsuya and the beginning of their friendship. Moreover, they've also presented other main characters such as Kira and Harumi.

The second and the third stories, Nemuru Raion and 1 Karatto no Kajitsu, are oneshots not related to ＭＡＲＳ.

The first tells of the strange relationship between Isomu, a guy who pretends to not have any fear, and Ayame, a girl with particular behaviours; on the contrary, the second tells of Nina, who has some family problems, and Rui, her classmate who is interested in a close friend of the hers. But what if he's interested in Nina?

Marriage Royale's story revolves around the male protagonist, a high school student named Tsukasa Hinomoto, who is told one day by his parents that he was adopted. Furthermore, they tell him that his real father is a manager of a large company, meaning he is very rich and holds a lot of power.

Tsukasa's real father wants his son to marry a good woman, so he sets up an event known as Marriage Royale. Beautiful girls from all over Japan will come together at a school built especially for this event and vie to become Tsukasa's fiancé.

The school is located on an isolated island near Japan, and Tsukasa himself is taken there to live in a mansion in the care of two twin maids: Miku, the elder sister, and Miu, the younger.

Doujin work of Aoki Ume. Sketches of her favorite anime and a short story about two girls.

After a long and treacherous journey, our Hero finally arrives at the Overlord’s castle only to find himself being asked for help. The Hero explains how the war that the demons have brought upon the humans have killed thousands and put more in misery. The Overlord however argues that this war has made the human society band together as one and showed empirical evidence how it has increased population, increased production, boosted economy and improved society overall. Furthermore, she explains to the Hero that ending this war will result in a civil war that will produce more bloodshed than there ever was.

The Hero, convinced that the only way to bring peace, relatively speaking, is to join forces with the Overlord, agrees to help with her plans!

Andou is a high schooler who possesses the ability to force others to vocalize his thoughts - an ability similar to ventriloquism. Inukai is young man shrouded in mystery who commands the vigilante group, Grass Hopper, which appeared in a city shaken by the downtown restoration program. This is a tale of courage, resolution… and confrontation; this is a depiction of the two boys’ encounter."Even if it’s nonsense, if you believe in yourself and face things head on, the world will change."This was dropped by Endless Abyss.Though it has 10 volumes (Completed) in Japan.

The great demon Mao Dante, exploiting the weakness of a boy exposed to his demonic influence in his dreams, is awakened from a thousand-year sleep. The intent of this being, a survivor of an ancient and forgotten civilization, is to wipe out the whole human race.
But it's not that simple: the motivations of the demon aren't so wicked as one might think, and they will combine with the life of the boy, which hangs between nightmares and craziness. In the meanwhile, the Satanists fight against the hierarchy of the church to obtain a justice which is, as it's easy to guess, that of the demon Mao.

This series didn't have an ending until its remake in 2002. Nagai took many ideas from Mao Dante into Devilman.

From Operation Boredom:
It is currently the Taiheimeji Era. It is a reign ruled by the Tokugawa shogunate. Inside this shogunate, there is a group of warriors that support the government. They are the Manyuu Clan. In this current era, breasts mean everything. If you have breasts, you are guaranteed wealth and popularity. If you lack them, you are rarely considered "human". Members of the Manyuu Clan help raise the future big breasts. Written on a secret scroll possessed by the clan, there is said to be various techniques on how to grow big and beautiful breasts. Chifusa is to be successor of the clan. However, she takes the secret scroll and runs away with it, hoping to fight against the cruel world that the Manyuu Clan has created.

What do two Japanese detectives, a naked man on a city street, and a roundworm from Botswana all have in common? In the first volume of Manhole, Ken Mizoguchi and Nao Inoue investigate a string of bloody and mysterious murders, but their work uncovers a deadly biological agent which poses a threat of epidemic proportions. An unlikely lead starts them in the pursuit of a mysterious self-titled photographer, but meanwhile the infections keep spreading. The series may be best described as the thrilling combination of a detective story with biological horror.

Kitajima from Reset has a guest role in volume 3.

Teddy, an apprentice carpenter, needs to tell something very important to a lonely sorcerer, Daaru. In order to do so, she decides to build a ladder to the moon.

From Echochi Scans:

Saitei na Anata to Aki no Sora (The Worst You and the Autumn Sky)
Nanami thinks his senior is a really awful guy, but still he can't help but like him. When his senior gets dumped, what will he do?

Sergeant Kai takes responsibility for the hardest missions, earning himself the nickname "Iron Heart". Kai claims that he's doing it for promotion but is there something more behind his ambition.....?

A mysterious creature named Million pops out of a normal looking black book and refers to itself as a great sorcerer! It asks the main character to be buddies with it but the main character thinks it looks suspicious!

"Let’s make a child together!!" is what a girl who appeared out of the blue said. A pretty onee-sama and a cute girl, middle school student Takao Reiichi’s destiny is going to change in a big way since he met these two girls! Was their encounter a coincidence? Or something is bound to happen? Falling in love with the opposite sex and friendship?! Here comes another new love comedy!

From ShedgeScans:

The daughter of a game shop owner finds a pocket game on the street. However, it was actually an invitation to a game of horror and slaughter!? The Game of Hell where humans are invited by the Shinigami as characters begins!

This series follows the adventures of two main characters as one of the characters goes through a series of episodes in discovering his female identity as a trap. This is a series in which each adventure is a self encapsulated oneshot not dependent on previous oneshots for a coherent understanding of a story to occur.

Collection of 5 short stories:

1) Mienai Kimi e no Okurimono
Tsuchiya Haruka comes from a family where the members are able to see ghosts meets a ghost her age at her school. The ghost quickly discovers she has a crush on someone, and decides to help her out. At the same time, she wants him to get over his attachments on earth, so he can pass on.

2) Like... Like... Like
Asami Niijima found out her boyfriend was two timing, and when she confronted him, he dumped her. She is determined to not trust boys again, until she meets Takumi. She quickly recovers from her break up, and falls in love with Takumi. When going out however, it seems he is becoming distant. What is this uneasy feeling?

3) Kiss Me... Kiss Me...
Ai is considered a real beauty by her peers at school, and they idolize her. Her boyfriend Yoi, with whom she has been dating for 3 months, doesn't seem to mind at all. In fact, he doesn't seem to care at all. This frustrates Ai, who begins to wonder if he really loves her. On top of that, she only started going out with him because he was persistent, as he isn't really her type. What will happen when someone (Katsuki) who is her type asks her out?

4) Come Beside Me
Gyouaki is a girl who always puts on a smile, and forces herself to be outgoing and funny at school. Out of nowhere, Araki, a boy from her class, asks her: "Aren't you forcing yourself?".

5) Out of Bounds
In a group of friends consisting of 3 guys and 3 girls, there is an unspoken rule that you do not go out with each other. Unfortunately, you cannot choose with whom you fall in love.

From Aerandria Scans:

In a world where people with green eyes are despised and named as bringer of plagues and destruction, Sue seeks a cure for her ailing friend. A holy nun comes into town one day to cure the sick and drive out the plagues. Due to desperation and lack of money, Sue decides to kidnap the nun to plead with her to heal her friend. What she didn’t bargain for what suddenly facing a green-eyed devil!

Meet Yohji and Iku, a couple of transporters (truck drivers) who have found a fun way of passing those long hours on the road. Meanwhile, their boss (who is quite amusing) is depending on them to make sure that they don't lose customers to a rival transportation company. Can they help keep their company alive?

from Dangerous Pleasure

Yohji older brother's story is at the end of Kishidou Kurabu Volume 2.

Soah is a lively human boy who dreams of becoming strong enough to defeat the Jotunn. He is also inspired by Thor, the heroic God of Thunder, who has patrolled around Midgard in order to eliminate all the Jotunns, protecting powerless humans, and Soah's friend. One day, after Thor returned to Soah's village for a short stay, Soah got captured by the Jotunn while he's training. Despite of his hesitation to attack the Jotunn because of the friendship they shared, Thor finally destroyed the Jotunn, but killing Soah as the result as well. Seeing Soah's determination, Thor bestowed all his Meging into reviving Soah, sacrificing himself. Several years passed by since the incident, Soah now is traveling out of his village along with three Meging weapons Thor left behind, in order to carry out Thor's will and protect Midgard from the Jotunns.

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From MangaHelpers:

In this story of Norse mythology, humanity's world of Midgard is caught up in a war between two of two powerful divine races, the Jotunn and the Aesir. Humans can't stand against them, due to the godly 'Megin' power of the divine races. The Jotunn see conquering Midgard as the first step toward attacking the home of the Aesir, and they slaughter many humans along the way. The Aesir step in to rid Midgard of the Jotunn and protect the defenseless humans. One of these Aesir, Thor, made his home base in a certain grateful human town.

In this town lives a young boy named Soah, who lost his parents in a Jotunn attack. He idolizes Thor and dreams of one day becoming strong enough to fight Jotunn and protect people. Thor enjoys Soah's childish enthusiasm, and the two of them share a warm friendship. One day, a Jotunn invading the town uses Soah as a human shield. Thor protects the town, but at the cost of the life of his young friend. Unwilling to let the strong-hearted boy die, Thor bestows his Megin upon Soah and vanishes. After much training, the now-powerful Soah begins to realize his dream, fighting against the Jotunn in Thor's place! [tethysdust]