In the era of the gods, year 300. Yuuna Yuuki lives an ordinary life as a second year middle school student, but she's also a member of the "Hero Club," where club activities involve dealing with a mysterious being called "Vertex."

- ANN

The number of humans has plummeted in a world where a deadly poison was spread by the explosion of a research facility. One day, Professor Murase discovers a girl who was preserved by a capsule. In a world where there are no young women, her existence has become the saving grace of humanity.

A young boy comes to an understanding about death.

Sengoku Rance is all about the most perverted hero of a fantastical world. He journeyed to Japan in order to have his way with the ladies of this land, and ended up as the secret ruler of Nobunaga House. In the process of conquering Japan, he unwittingly play the dupe for an ancient demon sealed in this land just waiting to be freed. Nevertheless, be it either demons or hostile forces, none shall stand between Rance and his ladies.

Civilization is dead, but Chito and Yuuri are still alive. So they hop aboard their beloved Kettenkrad motorbike and aimlessly wander the ruins of the world they once knew. Day after hopeless day, they look for their next meal and fuel for their ride. But as long as the two are together, even an existence as bleak as theirs has a ray or two of sunshine in it, whether they're sucking down their fill of soup or hunting for machine parts to tinker with. For two girls in a world full of nothing, the experiences and feelings the two share give them something to live for...

A journalist discovers a mysterious video when she becomes interested in the deaths of some local teenagers who attended the same high school. Only after watching the video does she realize that it is the missing link in the deaths of the teens. With just one week to live, she must solve the riddle of the accursed video if she wishes to save herself.

Wazu was an ordinary townsman who shut himself off in the “mountain” because of an unfortunate course of events. After 2 years, he decided to come down from the mountain to meet with people. But there were various misunderstanding about the “mountain” which he shut himself off in. And then he repeatedly had encounters with people. And after that...

4-koma about the funny moments of Hiroshi and his girlfriend's little sister Pon.

Sakura secretly loves her male coworker Sugi. But he's in love with Momoko, a regular client at the cafe who has no lasting relationships. Suddenly Sakura decides to confess to Momoko to go out with her! And to her big surprise, Momoko accepts to go out with her! What will happen now?

From Easy Going Scans
On his right, his index finger on a trigger. On his left, a wedding ring. That is Tokichi's new life. A shy and clumsy salaryman, forced to become a hitman overnight. A double life: bowing during the day and gunfighting at night.
He also has to juggle the two women in his life: his domineering wife and the jealous girlfriend he has inherited as his secret persona.

Its about a boy that one day, wakes up as a big breasted woman. S/he has to deal with a pervert friend, new clothes and a mother that prefers him as a girl.

Everything fell apart after the miscarriage of Nori's sister. Her husband left her and she was reduced to a depressed shut-in. One day she suddenly brought home a cute little girl called Yumi-chan, who was supposed to be her friend's kid. Nori's sister soon regained her smile, but Nori felt something was off with Yumi-chan, and the rest of her family.

Pro wrestler Fuji Kaoru disappeared one day during a match. Now five years later she shows up again at her old gym unnanounced, with her five-year-old daughter in tow. But not everyone is ready to welcome her back with open arms, especially her former best friend Yuri, whose anger and hurt at Kaoru's betrayal are far deeper than Kaoru ever imagined.

From DrCoke at MangaHelpers:

When Kamiyama Keito saw Oomiya Honden High School's (a.k.a. "Denkou") Rock Band "Kei-On" club, he was immediately struck by a sense of awe and admiration. Once he was admitted into the school, he immediately joined the club. To the despair of Keito, the club was run by two degenerate senior students who forbid any real practices. Once spring break turns around, Keito finds out that the two seniors were arrested for possession of marijuana, in turn pushing the club into the brink of termination. With the help of the only other member of the club, Tsukumo Shintaro, will Keito be able to prevent the termination of his club?

Lisa moves to Tokyo for university, and she finds herself living with some strange people! The Russian girl Irina explains that the inhabitants work on a time machine together. The other people include Kitsune (who wears a fox mask), Hime (who cooks), and Aki (a self-declared scientific high school genius). This 4-koma style manga follows Lisa's bizarre new life.

Young Ko is about to learn a new hobby...

Ko Higaonna, sharing a moment with his not-quite-girlfriend Satomi, is disturbed to discover a sallow-faced man watching with infrared goggles from the darkness. Ko's sense of privacy is offended, and soon blood is spilled, and the goggles pass into new hands. But the Voyeur remains, and now Ko is his pupil, about to discover what goes on beneath the smiles on people's faces... What goes on in private, in the dark...?

Yugami Makoto likes to travel to different Hot Springs. On his 100th visit to a Hot Spring he meets a beautiful foreign girl in the bath. Stunned by her beauty, he immediately falls for her. But there is more to the girl than meets the eye. And why is Makoto forced to work at the Inn afterwards?

Chiisaku Furikabutte, lit. “Small Windup”, was published in Afternoon between the tankobon publications of volumes 15 and 16 and during the 2011 hiatus, and it is a series of specials about the lives of Oofuri characters. (Nice Pitching!)