1) Saikou no Kimi
All begins when Soga Naoaki went to complain to the president of the student counsil, Yoshizumi Sekai, about the reducing of his volleyball team's bookings. By coincidence, Naoaki becomes the vice-president of the student counsil because of the health of the current one. He and Sekai don't get along, but what happens when they have to organise the school festival? Also found in Koibito no Namae

2) Kimi to Boku no Itsu Pobun
Oneshot also found in Renai Jikaku Shoujou.

3)Kimi ni Ai ni
Oneshot also found in Takaramono.

4) Afterword

Ikewaki Gajirou, nicknamed Gacchan, is the most valorous of the Big 5 in his school. He's a pretty good person. However, he has one flaw that people fear him for...

From Tokyopop:
On a world with no women, the surviving men have reintroduced the female in the form of an android. Called Marionettes, they are built to serve men and are limited in their interactions with humans. That is until a poor boy named Otaru Mamiya encounters a Marionette named Lime. Lime is a Saber model with a special circuit that gives her emotions. When Otaru awakens two more Saber Marionettes, his life as an 'average' man quickly becomes as extraordinary as the lives of his eager, busty new friends.

In search of her mother Nagi, a girl from a desolate country village, comes to a big city and enters Swimming Suieikyou High School. Shortly after joining the swimming club, Nagi finds out that the pool is actually completely overtaken by boys! But in this never-practicing so-called swimming club Nagi finds something...

22 years ago a mysterious seismic phenomenon rocked the Yokohama district, thrusting it miles into the sky and effectively separating it from the rest of Japan. In the following years, a fraction of the newborns in this fledgling world began to develop extraordinary powers, each unique to the personality of the possessor. These mutated humans became known as Alters and were responsible for turning the former Yokohama into a chaotic wasteland. Now, as the former metropolis continues to re-build itself, the Alters have fallen into two camps: those who have joined HOLY, a dogmatic organization that hopes to re-establish order and morality, and those who wish to lord over the comparatively weaker humans. Only Kazuma, a powerful Alter who's really only interested in looking out for himself and an orphan girl named Kanami, stands between them, suspicious of both sides and unaware that he may hold the key to harmonious co-existence.

From Yen Press:

Millennium Academy is a school where elite vampires are trained to maintain balance in a world where humans and vampires, who possess far greater physical strength than their human counterparts, coexist. And commuting to this school is Aldred, the most distinctly un-vampire-like vampire to be found in the entire institution. But when Al encounters Kei, a human transfer student to the school, their destinies become intertwined, and the fate of their world as they know it comes to lie in their hands!

From Evil Flowers:

Yamato, a boy who lives in Shirakami Mountain Village, Aomori; loves festivals. He visits the Tokyo Girls Collection, attracted by its title as “The BIGGEST fashion festival in Japan”. Although he doesn’t have a ticket, he manages to get inside. He encounters a fight between models, and successfully breaks it up. At that time, one person shows up and offers him an opportunity to work as a producer. Will Yamato be able to take advantage of this BIG chance…?!

Classic short stories from Takahashi Rumiko. Many are comedies.

Volume 1:
"Fire Tripper" (fantasy, romance)
A gas explosion sends high school girl Suzuko and toddler Shuu 500 years into the past. But she lost Shuu on the way, and as a result, Shuu ended up in the past 10 years before her, and is 15 years old when Suzuko arrives.
"Maris the Chojo" (comedy, sci-fi)
A destructive alien policewoman sees a kidnapped quadrillionaire as her ticket out of debt.
"Those Selfish Aliens" (comedy, fantasy)
Aliens, the government, and fishmen implant bombs in a poor paperboy.
"Time Warp Trouble" (fantasy)
Warriors from feudal Japan inexplicably pop into a high-school classroom.
"The Laughing Target" (drama, romance, supernatural, tragedy)
When they were children, Yuzuru Shiga and his cousin Azusa Shiga were engaged. Azusa aims to make sure that Yuzuru stays hers, no matter what, but Azusa also has a dark secret...

Volume 2:
"Wasted Minds (Dust Spot)" (adventure, comedy, fantasy)
Follows a pair of two bickering government agents, both of whom have special abilities. (A five-part mini-series)
"The Golden Gods of Poverty" (gag comedy)
An unfortunate boy's scientist parents try to use him to make money, but they only succeed in contacting the Seven Lucky Gods, who happen to also be broke.
"The Entrepreneurial Spirit"
A woman leads seminars for a get-rich quick scheme.

Volume 3:
"That Darn Cat" (slice of life)
Takahashi Rumiko remembers having to take care of her neighbor's cat.
"When My Eyes Got Wings"
A couple befriend a sickly child with a secret and his destructive pet bird.
"Wedded Bliss" (comedy, romance)
A wedded couple can only let out their tension from working all day by fighting with one another, until their neighbors threaten to have them moved.
"Sleep and Forget"
A girl relives a past life involving her lover and an evil witch back from the dead in the form of a dog.
"A Cry for Help"
A fairy gives a boy a frightening split personality thanks to the wind-up key she inserts in his neck.
"War Council"
Student councils go to war with one another over a stamp.
"The Face Pack"
A man can change his appearance at will and leads a "masters of disguise" club.

more info here.

1) Rumble Rush
New worker at the train station, in a desperate situation being played with by a groper. A groper, who targets only young men during rush hours, appears! And… the new staff at the train station Akiyama, who by orders to become the bait for the groper, gets to experience the attack of the pervert finger…!!

2) Dr. H!

3) High School Maze

4) Roar of the Sea (Shiosai)
Hirofumi returns home when his father dies. Will he meet his high school friend Jin who confessed to him when they were teenagers and was part of the reason Hirofumi hasn't returned home for 15 years?

5) Stay

6) After the Rain

The story revolves around Tsukune Aono, a boy who accidentally gets enrolled in a school inhabited by monsters and demons. He quickly befriends Moka Akashiya, a vampire who soon develops an obsession with his blood, and later meets other girls who soon take a romantic liking to him.

From Attractive Fascinante:

After his parents passed away, Aizawa Kyouichirou, a middle third year high schooler, rented out the 6LDK apartment in the form of room sharing as suggested by his guardian, Yagi Akira. The occupants were Rio Forest - a foreign college student, Mutou Keigo – a National Literature college student, Kawakami Shinji – a top host and Tachibana Jinpei – a workaholic. After they started to live with each other, they learned how to love and care for each other.

From Fantasyshrine:

What happens when Nagasaku, the president of the most popular cafe "Lotus" and Kouzuki, the number #1 host of the most popular club "Adonis" want to rent the same 2.000.000¥ lavish apartment in the exclusive King's Hill? Room share, of course! Two unlikely roommates agreed to co-habitate the same apartment with very strict conditions. Will this arrangement really work out between these two semes...?

Being a housewife is no picnic, especially if you have to deal with an idiotic hubby, two reckless children, a mother whose hobby is to decapitate moving “things” and those annoying zombies that are always out to have the best bite of you. A hilariously bizarre tale from the king of gag manga: Kenji Hamaoka of Urayasu tekkin kazoku (Super Radical Gag Family) fame.

4 Stories---The first and second story have the same heroine.

She works at a daycare center or kindergarten, and unknown to her colleagues she used to be a much feared female gang leader. ^-^ Also, the heroine has good vibes about a certain male colleague. One fine day, she meets an ex-male gang leader who knows her past...and events start unraveling from there.

For the second story, it's set in the daycare/kindergarten too. The main character is one of the kids in the kindergarten, and he has a secret which he is afraid to let other people know, especially his beloved teacher. (The heroine is his beloved teacher.)

Story #3
The main heroine is a 16 year-old girl. Her father is a scientist and always invents some weird things. What's more, he claims that he came from another planet! All these drive the poor heroine crazy ^-^ But at least now her love life is going fine...until the day 2 guys from outer space land on Earth, wanting to find out more about the 'Love disease'! Perhaps her father has not been lying after all?

Shizuka, age 17, was raised by her mother, and the two are very close. However, the store her mom's worked hard to maintain was swindled by the Sakurasei Real Estate Company.
Shizuka then, pretending to be the new wife of the president of Sakurasei, enters the Sakurasei family home while the president is away on business to get back the deed to her mom's store. In an instant she becomes "mom" to three boys, and the eldest son Kanon is the same age as her...

From Enchantment Scans]: Zhui-Ming (Shina in original) is just an average girl. However, due to a makeover, she accidentally gets mistaken for popular idol, Ai, by another famous idol, You. What's this? Ai and You are supposed to be dating?What is going to happen to Zhui-ming? (found in the series Panic x Panic )

from Blissful Sin: The president of my company caught me, Chisato, kissing another man somewhere. Luckily, my company ranking is so low he shouldn’t be able to recognize my face! I desperately tried to convince myself of that, but several days later, I was selected to be the president’s secretary. This is horrible, it seems like the president knows about my relationship with men!

The story revolves around Wakame High School's extracurricular club, "Sexy Commando Club," which consists of 5-6 male members (one being the high school principal himself), a female manager, and a small mysterious pet (that may be extraterrestrial in origin). The strange and ancient art of Sexy Commando (the roots of which extend back into Japan's Muromachi period) is a martial one; however, instead of focusing on how to defeat an opponent with punches, kicks, or grappling, it focuses on how to distract the opponent. The logic follows that any distracted opponent is unable to fight, and therefore the art of Sexy Commando trumps any other form of martial arts. There are as many techniques as there are ways to distract, though Wakame High School's Sexy Command Club tends to employ the unzipping of the trousers (Elize no Yuutsu).

From ShoujoMagic:

All Kumiko wants is to become a teacher; however her father is dead set against it. He is giving her one chance to prove herself as a teacher before forbidding her from pursuing this career forever. Meet her newest student, Ryu-kun. He has NO desire to LEARN anything from his tutors, rather he is an expert at teaching THEM about...SEX?!

Note: The story was originally released as a single short story, but it later became a series.

All of the girls at his college love Suou Tsukasa and come up to talk to him on a daily basis. Unfortunately for them, Tsukasa hates girls that are straightforward like that, but is too nice of a guy to tell them that.

In fact, he has a crush on Kizaki Megumu, his classmate and one of the shy and least talkative girls. The professor in one of the classes they have together is Dr. Hime, a young teacher whose childish looks and short height makes her a target for her students to jokingly tease and treat her more like their friend rather than a professor.

After taking home the drunk Dr. Hime, who was served lots of alcohol by her students, Tsukasa learns a giant secret about her love life.