From A Duck's Paradise and Easy Going Scans:

Doppelgangers. Mice that take the form of humans. With murderous intent, the look-alikes and the originals are both pressured to fight in their own ways. After an ambiguous event in their life, Jin-Uk and So-Hee's love life has been shattered. While trying to reconcile with her, Ji-Suk meets her look-alike, and that's how this story starts. What will he do when he, too, has a look-alike destined to kill him? And what's the secret So-Hee will never tell?

From Aerandria Scans:

In New York, behind all the hustle and bustle of the big city, Kazuya and Keith execute "requests" in order to live. No one knows about them. But what happens to people who look directly into Kazuya's jet black eyes?! For some reason, they start to change, little by little. The much-awaited first volume of a romantic horror story between light and darkness.

This is a strange love story about a genius who is unable to erase his memories and an average girl.

Mika, an average female high-school student, falls head over heels for her beautiful violin teacher, Akizuki, who has the uncanny ability of "never forgetting something he's remembered once."

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Includes other works:

- Lion
- Room 1/4: Penniless Cinderella

From Viz:

Kurôzu-cho, a small fogbound town on the coast of Japan, is cursed. According to Shuichi Saito, the withdrawn boyfriend of teenager Kirie Goshima, their town is haunted not by a person or being but by a pattern: uzumaki, the spiral, the hypnotic secret shape of the world. It manifests itself in small ways: seashells, ferns, whirlpools in water, whirlwinds in air. And in large ways: the spiral marks on people's bodies, the insane obsessions of Shuichi's father, the voice from the cochlea in your inner ear. As the madness spreads, the inhabitants of Kurôzu-cho are pulled ever deeper, as if into a whirlpool from which there is no return...

From Storm in Heaven:

In the town that Takada Chinatsu moved to, there's a legend about demons called Tsumitsuki that possess the feelings of guilt a person has over their sins. Those who are possessed are slowly devoured, body and mind, as the demon manifests. As one of Takada's friends starts acting strangely, her classmate Kuroe steps in to help... but his true motives are hidden behind a mask.

From Hyper Parfait:

After World War III, the Führer established the Unified World Government. Anything considered as damaging to the creation of the “Perfect World” is eliminated, such as people with disabilities, believers of a different religion, those that are considered as “traitors”, and so on.

The Black Rose is the personal protection guard unit of the Führer. Luka Ogami, the top graduate of the academy of unified army officers, joins the Black Rose…. to save the world.

Paraphrased from Kotonoha:

This is a collection of eight stories (there are 9 chapters, because story 6 is composed of chapters 6 and 7).

Story 1: Teased and Stepped On, What Blooms is a Passionate Flower
Describes the relationship between a girl and her teacher.

Story 2: Lolita #7
Features the relationship between two cousins, an older male and a younger girl. One is a teacher, while the other is a student -- both at the same school. When the elder cousin doesn’t come to class for several days, the school administrators send the younger cousin to the elder cousin's home to investigate further.

Story 3: Song of the Devil

Story 4: What If?

Story 5: Happiness

Story 6: A Room of Clouds (chapters 6 - 7)
A simple minded girl who tries to live her life the best she can.

Story 7: Indigo Elegy

Story 8: Underground Doll

This coming-of-age story is about two people, Sae Tae Han, who is unemployed, and his new roommate, Woo Min Kim.

Yugo Beppu is a master negotiator and mediator. Fluency in five languages, Socratic wit, and a deep understanding of human nature combined with top-level international connections make him a formidable operator. When a woman's father is seized by Dacoit bandits in Pakistan, Mayuko seeks Yugo's help. After complex and dangerous negotiations, he secures his release. After this success Yugo is called in to deal with yakuza in Japan, triads in Hong Kong, the IRA in Northern Ireland, and the Russian Ministry of Internal Affairs in Siberia.

Note: New versions of this manga were published under different arcs in bunko format such as the Pakistan Hen, Russia Hen, etc.

The main protagonist, the shy Jun Naruse, is a rather average guy who works for a electronic company and loves to draw. He falls in love with Megumi whom he met at a shop selling drawing materials and an intimate relationship develops. A few days later the office gets attacked and when the criminal tries to shoot a little girl he saves her by jumping in front of her.

A month passes until he wakes up again and is told that half his brain got destroyed and he only survived because someone donated half a brain. Everything seems to be fine, he quickly recovers and is happy, however he begins to change... is the donated brain the reason for that? Or is it just a side effect of the medicine?

One-shots included in volume four:

• Area
• Yasokyoku - Nocturne
• Body

From Aerandria Scans:

Rinko is an ordinary girl who was born with a mysterious birthmark on her left arm. But when that mark starts to get darker, strange accidents begin to happen everywhere around her, involving even the people she cares about. What will the powerful magic awakening inside Rinko bring her?

In 1987, Purple Eyes in the Dark was awarded the Shogakukan Manga Award for the shoujo manga category.

Later it got a continuation: Yami no Purple Eyes - Bangaihen - PANTHERS.

From Shoujo-Sense
Nothing in Sakiko's life seems to be going right. Frustrated with her job and nursing a broken heart, she embarks on an ocean cruise, hoping the change of mood will turn things around for her. Never does she expect her vacation to end with the ship capsizing, stranding the surviving passengers on an island. When a young man saves her life, she finds herself drawn to him, but soon discovers he may be harboring a dark secret...

Yuuto Sasaki is a trap who forces his homeroom teacher Sasaki Tsukimori to spend some quality time after school, which usually entails Sasaki playing a domineering role over Tsukimori.

Note: Original language image is not available.

Nana, an apathetic 24-year-old with nothing much in her life, suffers a car accident and wakes up in her 14-year-old junior high body. As she lives through each day, she starts to remember things she buried deep in her memory, and she can now not remember being involved with her older sister, whom she deeply admires, and her sister's first love, a senior at her school.

Explore the lives of the famous-yet-not-so-famous people of history; such as Nikola Tesla, Ty Cobb, Typhoid Mary, the woman behind the Winchester Mystery House, Kou Yoshio, and many more.

Series of one-shots published between 1989-2003, released a tanko volume in 2004 and a bunko release in 2012.

From Houkago Scanlations:

Shiki threw everything away for the sake of revenge. But at the new school where she disguises herself as a male, she meets 4 popular rich guys... Haru (spring) the prince, Natsu (summer) the bishounen, Aki (autumn) the womanizer, and Fuyu (winter) the cold-hearted genius.

What awaits Shiki? And will she get her revenge...?

Hayate and Kusanagi are best friends. They are pretty popular in their high school, and they always attract a lot of "unwanted" attention because of the ambiguous attitude that Kusanagi harbours sometimes torward Hayate. Invited both to a students counsel's sponsored meeting about UFOs, they stumble upon Hayate's little brother, Tatsumi. Hayate gets into an argument with him because he thinks Tatsumi shouldn't be there. And Hayate didn't know ho much he was right, when, after the meeting started: a UFO crashes nearby the student group...

From Brolen:

This is a horror/sci-fi story about a giant planet consuming creature from another dimension that a scientist discovers and mistakenly identifies as a planet. Being given the honor to name it as its discover, the professor chooses to name it after his only daughter, Remina, but when Hellstar Remina is headed on a direct collision course with Earth the world goes nuts and all the people in the city start a witch hunt to kill Remina, thinking she is somehow to blame.

Main Story and 2 extra chapters :

1) Hitomi no Honne (3 chapters)
Hitomi's love life is a royal mess. First the sempai he has a hopeless crush on (Morihito) is getting married. Then while getting his heart broken, Hitomi is harrassed and felt up by sempai's perverted cousin - Tatsuya! Just when things seem like they couldn't get any worse, Hitomi finds himself responding to Tatsuya's touch.

2) Tatsuya no Honne
Flashback to Hitomi and Tatsuya's first meeting told from Tatsuya's perspective.

3) Epilogue to a Happy Ending (Happy End no Tsuzuki)
Continuation of Akira and Daichi's story from Miserarete (+ Tatsuya's cousin, Morihito).

Student still torturing his beloved Sensei and we get to know more about Tatsuya's past (partly from Miyata), that made him who he is. Will Hitomi still love (and understand) his student after hearing his story?