From Chibi Manga:

In that world, there are popular people and not popular people. That’s what that Miya-kun told Rui (17 year), who is not popular, after he dumped her. But what kind of girl will replace her…?!

Kiichi is a naïve university student who can't shake off his Okayama dialect. Coming to Tokyo to live and enter university, he lives in a shared house accommodation with 7 other residents. The urban, good-looking salaryman, Arima, whom he meets there, takes good care of him and is kind and dependable like a big brother.

Since jumping into the bath together almost immediately on the first day, Kiichi has been extremely unsettled by their overly close relationship. Kiichi can't stop the feeling of quickly becoming attracted to Arima, thinking "It's gonna be tough if I'm spoiled like this!"

A boy trying to commit suicide finds a zombie girl that tries to stop him from killing himself.

Himoto Sora is a transfer student with a sense of justice and dreams of becoming a knight. Upon arriving at Utopia Gakuen, she learns of a virtual reality-like game played by the male students in which they use girls as weapons in battles for status and treat them as commodities. Seeing one of these girls being abused she steps in and through some sort of error unwittingly becomes the first female participant of the game.

Republished in 2017 in a 3 volume omnibus
1) Shitsurakuen - Hangyaku no Otome no Shou
2) Shitsurakuen - Shinai no Otome no Shou
3) Shitsurakuen - Rakuen no Otome no Shou

From Sumie:

A love story between two souls separated by their stations in life, in the form of a tattoo.

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"Even if we stopped seeing each other, my soul would always be with you."
A man visits a certain tatoo artist. A vivid love story of surreptitious, yet intense longing of two souls.

Chapter 1: Shirube no Michi
Mao's life is far from normal: she attracts spirits and constantly has to keep her father from losing his soul! One day, she meets a man who claims to be a "guide for lost souls" and explains that he has come for her father!?

Chapter 2: Illusion Orangery
Mao's still working for the mysterious spirit guide. One fine day, the smell of oranges lingering in the air accompanies our young psychic on an odd game of hide-and-seek in a haunted house.

Chapter 3: Heaven's Fairy
Shinobu’s plans for the summer are ruined when her mother sends her off to her grandparents' countryside home. Bored and friendless, she prepares herself for a joyless vacation, but soon discovers that she has something in common with her grandfather: something quite magical!

Chapter 4: Foxfire
Miya knows she was found abandoned at a shrine and adopted by her current parents. Though she lives a happy life now, her birthright comes calling on her one day in the oddest of fashions.

Chapter 5: Box
"As long as these white walls confine me, I am safe."

Chapter 6: Angel's Ladder
The twisted - but oddly touching - relationship between a healthy and normal girl and her sickly and spiteful older sister.

Note: These oneshots ran in different magazines categorized as josei, seinen, or shoujo. The majority of them were josei, hence the demographic of the series.

From inmeliora:

Eight years ago, Mio, the princess of the White Kingdom, and Sakuya, the second prince of the Dark Kingdom, became friends when she got lost in the forest and Sakuya helped her. They were friends until one day, three years ago, she was sucked into a hole and went missing, and Sakuya is determined to find her. In the three years since her disappearance, he became friends with her older brother, Rui, the second prince of the White Kingdom, even though their two kingdoms don't get along. One day, while joking around, a hole opened up in the sky and a girl fell out of it. Sakuya had dreamed this would happen, but who is this girl and why did she fall into heaven?!

Ririko lost her parents and siblings in a mysterious incident where details remain in the shadows. Before Ririko moves to her new home in Kaminoshiro, a detective gives her a letter that her father wrote before his death, which contained a card with a black and white checkered pattern on it. At her new school, Ririko becomes friends with Maya and has some interest in a male student named Shirou. She questions about the black clock tower that stands in the center of the town, but no one bothers to answer the question. Her new life in her new home seemed all as well until one day Maya calls Ririko out and takes out the same checkered card that Ririko was given to her and she summons some unknown creature! As Ririko is in confusion as to what's going on, Shirou appears and says "Not another one..." What's going on around here?

In this story set in the early 1980s, a young man dreams of becoming a renowned comic writer in years to come. His name is HONOO Moyuru. He has no money, only a dream. Then, he feels overwhelmed by his lack of ability, and buys some sake, although he has no head or stomach for alcohol. This is a tortured elegy for any dashing young art student who spends his days careening around in burning ambition. Note: Was nominated for the 3rd Manga Taisho Award in 2010 and for the 19th Tezuka Osamu Cultural Prize in 2015. 

From Evil Flowers:

1) I should have...
En Asakura often has the same dream lately. She dreams of a boy asking her to kiss him. Her dream is connected to a painful memory from her high-school life, when she felt in love with a boy named Maru. When he asked her to kiss him, she refused, and now she's regretting it. Not to mention that the boy started to date another girl after that incident.

En is now in university and is trying to find her life partner through goukon: blind group dates. What will she do when a boy with the same name as her past crush asks for her number? Will she refuse and regret it again?

2) The Realization Of Happiness
Continuation of the preview chapter.

3) After School Kiss

4) Tell Me You Love Me

5-6) My Friend's Boyfriend

Follow the friendship of Tetsu and Gorou from the Koushien to adulthood.

A strange phenomenon where one is transferred back to the moment right before something life-threatening occurs. This continues to happen until the cause of the threat is erased. It is as if somebody is forcing Satoru to stop it from happening. Then one day, everything is changed. What truths are revealed when Satoru comes face to face with his own past? How will they affect his future?

Boku dake ga Inai Machi: Re (Gaiden volume) is considered volume 9 of the series

Note: Was nominated for the 18th Tezuka Osamu Cultural Prize Reader Award in 2014 and for the 7th, 8th and 9th Manga Taisho Award between 2014 and 2016. Also nominated for the 40th Kodansha Manga Awards in 2016.

From Stage Storm:
Seiko is a normal girl with a tendency for daydreaming, and Yoshito's a fairly sensitive, subdued boy. They've been close friends since grade school, and now that they're in high school, their feelings for each other become complicated. Though all of the diverse array of characters in the story seem to see it as plain as day, Seiko does not realize Yoshito would like to be more than friends.

From Aerandria Scans:

Shiro is a white crow. Because of his unusual color, he's often bullied by the other black crows. One day, he's hurt badly because the others ganged up on him, and he was saved by a girl. Moved by the girl's gentle heart, Shiro asked a devil to let him turn into a human. However, there's one condition: Shiro will have to do at least one bad deed a day, otherwise, his body will crumble. Can Shiro really fulfill this contract?

In this direct sequel to Shiritsu St. Cattlya Youchien, we follow the story of teacher, Kuroda Shuuichi, and his adorable students as they move up to elementary school. Excited to be moving towards becoming a real teacher, Kuroda leaves the preschool only to learn that his new position is the elementary school with his old students. The incredibly unique kids are back including the Fuurin and Katori twins, the cheerful Miki, the shy Tsumugi, calm and collected Nazuki, and the panda hat wearing Daniel. The adorable yet weirdly mature children will capture Kuroda sensei’s heart once again.

A one-volume work containing 4 stories total, including the title work "Shiranami no Illusion"

- Shiranami no Illusion
Ryo is a boy who loves flirting with girls. One day, he met a beautiful girl named Touko by the beach. Ryo is soon deeply attracted to Touko, but because of an incident where her fiance died in a tragic accident, Touko locked up her own heart. How is Ryo going to help Touko leave her sadness and pain?

From Wasurenagusa:

As a child Tanabe was always tagging behind Haruyama, but in high-school after he became a ping-pong ace their relationship is gradually getting worse. Who is the one tagging along for real and why is Tanabe always so quiet? A touching and yet funny story with ping-pong as its background.

This volume also contains a one-shot about one very interesting hairdresser and a two-chapter story about a dentist and his fated client.

He possesses a mysterious power. His job is to remove curses from others.

Whenever abnormal situations arises, Zigzag is called to work. He accepts, however, it's not out of goodwill...?

A story about a hero? Definitely not this person!

From Tokyopop:

Legends say that when it snows, it is because the snow princess is crying. A collection of five tragic tales, all connected by the bond of snow. Shirahime-syo is CLAMP's tribute to traditional Japanese form and storytelling.

From Aerandria Scans:

This series is the continuation of Ookami ga Kuru! In order to investigate the strange phenomenon occurring in Northern Bayern, Germany, the church (KIRCHE) have dispatched the slayer Sirius. He rescues a young woman, Beate, who was being attacked by zombies. However, as the two attempt to leave, they’re attacked by more zombies.