Many Shonen Jump characters have big dreams, but this character's big dream is a nightmare! A very realistic reoccurring nightmare where a giant monster destroys a city. And it always ends with Ko, the poor dreamer, getting crushed under the rubble. But when Ko meets an unusual man who somehow knows about the monster in his dream, his nightmare takes on a whole new meaning.

From asdf scans:

In order to live a normal high-school life, Mirei started her first part-time job. But after receiving her first paycheck, she almost kills a highly-ranked bishounen…?! An encounter with a super poor and pessimistic innocent girl, is this a beautiful miracle?!

From Chibi Manga:

That was the first time I fell in love. The first time I met "Leopard-kun", time stopped and I could not breathe. My heartbeat became louder and I could not take my eyes off of him. Although Leopard-kun told me "he wants to be with me", he is a guy who has kissed many girls. This love has many difficulties... it's tender yet painful, but even so I can't stop my feelings for him. I'm sorry...I fell in love with a "beast". This is my first love.

Tezuka Kanna, 15, is a girl who loves manga. For that reason, she specifically enrolls in a course for manga in Tokiwa High School as a freshman! No one knows though, that she is already a debuting manga artist. ...But wait, what's this?! Three handsome guys suddenly appear, and what's more they know!!! Kanna (God) vs. Those Guys (Devils)!!! What would happen next?!

Anthology Comic of Slow Start

Yukino Tachibana is a calligraphy prodigy.

At the tender age of 16 she is already one of Japan's most exciting young artists, performing live calligraphy demonstrations to sell-out crowds on worldwide tours.
With her refined, beautiful, and mysterious air, she is so popular at her new high school that she has earned the appellation of 'The School Madonna'.

She is also as dumb as a post.

As artful her brushstrokes, as demure her outward demeanor, the real Yukino Tachibana is far-removed from the image her classmates see on television and in the school hallways - in reality, apart from her calligraphy genius, Yukino is completely useless, rude, and possessing of a distinctly inflated sense of self-worth.

There is only one classmate who fails to be fooled by her facade: run-of-the-mill protagonist du jour Tarou Nakamura. Sitting next to her in class, Nakamura doesn't really get why the rest of the school finds her so enthralling - he's much more interested in his crush, Amano-san. But this indifference might prove to be his downfall, as circumstances cause Yukino to set her eyes on him....

This boy, this poor, poor boy, is burdened with a Herculean task - to keep Yukino's true nature a secret from the rest of the school, while trying to win the heart of his sweeheart. Can Nakamura really keep this brainless beauty's utter idiocy a secret!? And can he win Amano's heart through the power of calligraphy at the same time!?

From Shinnen:

Naraka High School is a seemingly normal school. However, unknown to the public is the cruel truth of what really goes on in the school's halls. Rather than studying, students are forced to struggle for their very survival. And the strong bonds of friendship may be the only difference between life and death.

Ryuuko Matoi is a girl who travels with a single red scissor blade, searching for the wielder of the other blade who killed her father. She arrives at Honouji Academy, a high school that lives in fear. It is ruled over by the fearsome student council, led by the student council president, Satsuki Kiryuuin, who use powerful uniforms to crush anyone in their path. After suffering a crushing defeat at the hands of Satsuki, Ryuuko comes accross a possessed school uniform named Senketsu, who puts himself on Ryuuko, granting her special abilities. Teaming up with Senketsu, Ryuuko stands up against Satsuki and the student council to liberate Honnouji Academy from their iron grip and find out the truth behind her father's murder.

Taichi Yamada is what you would call a fan but he is not just any fan, he is a fan of Kokoro Shiina, a gravure model. Maybe it was fate that brought them together that day but Taichi met Kokoro when she literally fell from the sky. Waking up in the hospital, he begins to see Kokoro's spirit and after roaming the hospital premises a "shinigami" arrives to take Kokoro to the underworld. Is this the end for Kokoro? What will Taichi do to save his beloved idol?!

Seven years ago, Yuto's older sister vanished through a mysterious door, leaving him with only a necklace. Now he has once again seen that same door, and watched two mysterious girls (Saya and Hina) go through it. Eager for clues about his sister's disappearance, he and his pet cat follow them through. However, he soon finds there's a reason his sister wouldn't let him come with her. In the deadly world on the other side of the door, his ignorance leads to tragedy. Now Saya insists that he travel through the door once again, to search for a way to retrieve the lives that he caused to be lost during his first journey.

From Chibi Manga:
We were sharing the same feelings but he didn't realize it at all. Even so, I love him. That's what I have always thought for these past two years.

From Seven Seas:

Welcome to Ansullivan Dragonar Academy, a school with a difference: the students are dragon riders, each contracted with their own personal dragon. Ash Blake has the unique ability to ride anyone's dragon, but he's been waiting for what feels like forever for his own dragon to be born. He's thrilled when his dragon, Eco, finally appears--but she inexplicably takes the form of a beautiful human girl.

Eco's peculiar appearance is only the first unusual thing Ash faces. His life is about to become a whirlwind of spies, dragon races, and unexpected attention from both the proud Princess Sylvia and the beautiful president of the student council, Rebecca. All Ash wants is to acclimate Eco to the world, but someone out there wants his strange dragon on the dissecting table!

The first year middle school Student Council Chairpersons (iincho) come from different elementary schools and different backgrounds. These six cute, glasses-wearing middle school girls often fight, but they have a common enemy in the sexual-harassing Student Council President. Will they be able to do their job without being distracted by infighting or thwarted by the controlling Student Council President?

The Planet Group is formed of powerful families that represent each planet in our solar system and the central Sun Family. Midori is the eldest son of the Earth Family, who is just now entering his high school life in the Planetary Academy. Other than his family name, however, Midori has little going for him. He doesn't get good grades and is shy and socially awkward.

His low self-esteem isn't helped by the general disdain his father and younger brother openly show towards him. All they want is for him to not further "dirty" the family name, by staying silent and not standing out in public. But at his new high school, Midori is surprised by the kindness of the other Planet children, particularly Yuudai Jupiter, who takes Midori under his wing on the first day. Will attending the Planetary Academy mark the beginning of a change in Midori's life, or is there no hope for him after all?

Jinguuji, who‘s not coming to school, is the most “talented“ in his grade. To get this son of a yakuza to attend lessons, Yuuki, the assistant teacher in charge visits him at home. But when Yuuki gets the attention of Jinguuji, who is with a girl, the latter suddenly gets aroused and forces Yuuki to sleep with him….! Is there a “family secret“ Yuuki‘s not allowed to know hidden in the ferocious eyes of Jinguuji who‘s devouring Yuuki‘s body —? The long-awaited manga-version of the popular “werewolf“ love story ♥ Presenting you the comic & novel with plenty of erotic scenes!

A big forehead. A big smile. That's how Maru and Miyaji met each other. They quickly become friends and as it always happens, they start falling in love.

It's been 25 years since the start of "Crows", a seminal work in the delinquent manga genre! This volume is a collection of 8 stories written by various authors as a tribute to Crows.

A poison-attribute heroine makes her appearance! This chaotic, high-school comedy focuses on the circumstances of this poisoned, poisonous girl and the unusual people surrounding her!

The future, romance, everything is "undecided", yet the remaining days of high school seem as if they'll be over in the blink of an eye. Ichimura Mikako, 17 years old. Midorikawa, the strange guy who now sits next to her after a seating change and oddly prefers red pencils. At first, Mikako didn't think much of it, but after learning that they both love the same band, their relationship begins to change bit by bit...

The day-to-day life of a 17 year girl woven together in a soft literary style.

A Keio College (top notch Tokyo college) exam candidate, Touma Inaba, is interupted when a cute young girl, Urara Kasuga, arrives at his hotel room door. She later turns out to be his cousin who he barely remembers from his childhood. Urara, who had felt something special for him (an other-than-cousinly-love), invites Touma to live with her since he has no place to stay other than the hotel room. Before taking the test, Touma meets Meiko Yotsuba, a beautiful, sophisticated woman also trying to get into Keio. Meiko gets into Keio but Touma does not, due to a cold Urara had given him shortly before. Although he did not make it, he pretends he does to earn the respect of Meiko. Touma is caught up in a love triangle with Urara and Meiko, while struggling to keep Meiko believing he's really a Keio student and still be there for Urara at the same time.