The series began as a fairly humorous and lighthearted satire of Japan's teenage delinquent-gang subculture told from the perspective of Matsushita Tadashi (who also narrates these early Karate Bu stories), a 2nd year student at Kangokou High and a constant target of Kangokou's numerous bullies who beat him up routinely after school. He is almost always accompanied by his best friend Saitou Takaki, who is also constantly harassed. As the pair grow increasingly tired of being victimized they decide to join the titular Karate Club, which is notorious throughout Osaka's youth gangs for training and producing the city's most hardened and toughest teenage thugs while maintaining the facade of a legit school sports club. But when they join the club, they find themselves picked on just as much if not worse by the club's current members. But as the story progresses they grow to be increasingly capable fighters.

As the series went on it gradually changed its tone to a more serious and violent martial arts manga, with the narrative shifting from the perspective of Matsushita to Takagi Yoshiyuki, the smart mouthed, tough-as-nails captain of the Kangokou Karate Club.

Along with the manga's change in attitude and central character, the various teenage fighters throughout the series grew increasingly stronger and even began to tap into superhuman ki abilities, putting Osu!! Karate Bu in the company of other similar epic Shōnen fighting manga such as Yu Yu Hakusho, Dragon Ball, and Fist of the North Star.

Osu!! Karate Bu was wildly popular in its native Japan, but is otherwise almost completely unknown in most other countries. It spawned a four episode OVA mini-series released over a period of two years from 1990-1992, a 1990 live action movie, and a 1994 Super Famicom fighting game.

From Antebellum Scanlations:

At the start of high school, Takae fell in love with Araki. However, Araki just happens to be indifferent to love. Against her better judgement, she begins dating someone else, but that relationship turned out to be a big mistake...What will become of Takae's love!?

From JShoujo Scans
Includes an extra story:
"Yori-chan has a Love That'll Never be Requited"
(Sequel to "Like Snow Falling on Harbor" from A Rose-Colored Tomorrow)

It's been over five years since Yori watched the car that his best friend and Kurita, the girl he was in love with, were riding crash into another car, leaving Kurita in a coma that she hasn't come out of since. His best friend, who had also been in love with Kurita then, has already moved on and found himself a new girlfriend.

For Yori though, time stopped that horrific day many years ago. Can his distant cousin, a spunky teenage girl who harbors a huge crush towards him, make him realize that it's time to let go?

From Aerandria Scans:

Serika is your typical high school girl. She loves reading books, likes romance, and has the ability to knock a guy flat out with her fist. She imagines herself as one of those heroines she reads in books, a shining maiden waiting for her prince. But what happens to her dream when the prince she has been waiting for is not only younger than her, but also smaller? Will the princess accept the chibi prince?

Otaku and Fujoshi—natural enemies that fight ceaselessly online but ignore each other in real life. But for this otaku and fujoshi who eventually marry one another, this is their love story!

Due to family reasons, Zongzheng Yue completely loathes otakus. He was originally living an ordinary life, but littering a soda can on a certain day triggered a series of events, and made a nonsensical girl who professed to be an otaku god enter his life. Under the otaku god’s instructions, Yue has no choice but to start learning how to become an otaku. Then, his loli senior and childhood sweetheart also began to enter Yue's life under the supreme otaku god Lan Ling's "interference".

Kanau Yukimura is nine years old and she's meeting her father for the first time. However, he turns out to be an otaku! The two of them start living together in the same apartment, next to a lot of interesting neighbors. Unsurprisingly, things don't always go smoothly for these two...

Ever wondered about the daily lives of good-looking kids whose parents are Otaku?

Yangwei, a kind and tall boy, is oblivious to the Otaku culture. On the other hand, Xiaoqi, the girl who sits next to him at school, grew up knowing it all due to her parents' influence. With Yangwei's and Xiaoqi's parent(s) being geeks, the two see each other in common and discover what's latent to them.

Otakura is a high school boy who's clearly an otaku, and Narumi is a high school gal. Normally, these two polar opposites would never cross paths, even at school. But by a strange coincidence, it turns out Otakura is able to use his inherently handy nature to help out Narumi with her own hobby-related requests, one after another?

Tamotsu walks in on his girlfriend with another guy, and finds out she's been seeing 4 other guys. In his drunken state, he calls up a delivery dating service, and got someone who he wasn't expecting. Delivery boy Asahi stays and listens to his problems, but after a couple of drinks it leads to something more.

Without really understanding what was happening, Rhea was chosen to be one of the fifty "apprentice hero" of the kingdom. Despite the apparent mistake, she unwillingly accepts this new adventure, armed with her manual under her arm. Right after bidding good-bye to her best friend, she encounters 2 weirdos who will quickly become her comrades, as well as the mysterious Burn, another apprentice hero who seems really skillful.

Ayumu Mikoshiba is a boy in junior high whose family runs an old shrine with few worshipers. In an effort to revive the shrine, Ayumu's parents decide he'll be the next in a long line of magical girls in the Mikoshiba family. Together with Fuu-chan, a small fox-like mascot character, Ayumu tries to help people while cross-dressing.

N/A

A freshman at Yuasa's college who's studying craft & design - Satoru Arimura - is a seriously perverted hand fetishist. Their hands accidentally brushed in the library, and now he thinks it's fate! He says Yuasa has "the hands of his dreams," and keeps coming to see him (well, his hands) every day, bugging him for photos, sketches, and studies!! While annoyed at first, Yuasa realizes how serious Satoru is about his craft, and ends up letting him sketch his hands. One day, Satoru sees Yuasa cut his finger, and insists on licking the wound to "disinfect" it... which makes Yuasa's heart race! Although, Yuasa does freak out at the bulge in Satoru's pants while he's going down on his finger!! Satoru's laser-focus on Yuasa's hands starts changing to an interest in Yuasa himself, while Yuasa's getting frustrated at Satoru's fixation on his hands...... Will their relationship take a turn for the romantic......? Find out in this love story spiced with freaky fetishism!

from Renta!

From Biblo Eros:

Love blossoms between a weatherman and his cameraman!

Sakurai Kyouta is a student in the second grade of a prestigious high school. He is suddenly assigned to be a chairman of the students council, instead of Mikami Kei, a very beautiful, respected and intelligent vice-chairman. The members of the council are cold to Kyouta because of that and Kei says to him "You are just a symbol. I will do everything instead of you". But Kyouta still tries to be as good a chairman as he can. When he is nearly raped, Kei saves him and orders Kyouta to be his pet in return of his support with the council work...

Otsu Hiyori's two-part one-shot "Othello" is about two girls who are opposites.

Yaya’s high school friends haven’t been very nice. They call her “Yaya the cry-ya! Yaya the misfi-ya!” But no matter how badly they act, Yaya is just too naïve and trusting to believe the worst of her friends. Hard-rocking, butt-kicking Nana is just the girl to grab hold of Yaya’s timid demeanor and turn it upside down. Nana exposes Yaya’s “friends” as slime bags, doles out punishment, and does it all with style. Can there be anything that terminally shy Yaya and hyper-confident Nana have in common? Well, for one thing, they’re the same person. -- Manga Updates

There are dangerous monsters called D's, lurking in the shadows of the world. A D mimics its victim's form exactly, allowing it to kill its victim and take its place. Kei, a normal high school kid, learns of these creatures when one of them targets his childhood friend Hinata. In his effort to protect Hinata, Kei finds himself being dragged into the affairs of Othello, an organization formed to bring about the extinction of these creatures.

Consists of four stories: 1) Othello- After Atsushi dies in a horrible accident, his twin brother Ayumu decides to steal his identity and returns to school in his place. He attempts to hide his reckless behavior and assume persona of his honor student brother. However, for some reason, Ayumu is unable to hide his true colors and composure around his classmate Kirishima. 2) Snow White in Summer- Kaoru returns to his child home to find that his once quiet and shy childhood friend Snow is now loud, mean, and violent, and the change is somehow his fault. 3) Night's Fragrance- masanari, and journalist, is sent to investigate the life of a popular and elusive artist, Sougetsu Tokiwa. While investigating, he comes across a beautiful and enigmatic boy whom is rumored to be Tokiwa's lover. 4) Night's Abyss (Haruka no Fuchi)- After the death of his wife, a man moves to the countryside and finds horror.