Oneshot from NisiOisin and Kawada Yuuya:

A boy suddenly wakes up to find out he's in the body of a high School girl. Who is she and how did he switch bodies?

Walkure Romanze's story revolves around Takahiro Mizuno, a student studying at an academy with jousting as its main focus for sport. Takahiro acts as an advisor to the riders of the sport. Takahiro goes through each day tediously until the time of the annual competition draws near. Due to some odd circumstances, his childhood friend Mio Kisaki is enrolled into the competition. As she has never even rode a horse once in her life, Takahiro senses the fear in his friend and becomes Mio's coach.

Stories of Beautiful Fighters from the Queen's Blade franchise made to suffer crushing defeats by various opponents. The events of all these stories are entirely non-canon and left as 'What If' possibilities instead.

Space Dandy is a dandy in space! This dreamy adventurer with a to-die-for pompadour travels across the galaxy in search of aliens no one has ever laid eyes on. Each new species he discovers earns him a hefty reward, but this dandy has to be quick on his feet because it's first come, first served! Accompanied by his sidekicks, a rundown robot named QT and Meow the cat-looking space alien, Dandy bravely explores unknown worlds inhabited by a variety of aliens. Join the best dressed alien hunter in all of space and time as he embarks on an adventure that ends at the edge of the universe!
from Bandai Visual

Ayase Yukiya is a university student whose cousin Tetsuo Ishii betrays him and sells him in an auction to settle his heavy debts. Ayase is bought by Somuku Kanou for 1.2 billion yen. The reason behind Kanou doing this is Kanou remembers Ayase from four years ago, when Ayase, a stranger, helped him. Now Kanou wants to keep Ayase close to him in order to protect him, and uses the 1.2 billion debt to force Ayase to live with him. As Ayase is still a student and does not have a job, he is forced to sell his body to Kanou for 500 000 yen a time.

From Cidsa:
A spaceship lands on a bathhouse which belongs to Kazuto's family. Inside is Princess Warukure (Valkyrie) who gives part of her soul to Kazuto to save him from death (caused by her crash).

Since she only has half of her soul, she turns into her child self. Now Kazuto and company must figure out how to fix the bathhouse and change Warukure back to normal.

Nurunuru Pharmaceutical’s leading product, the Piagra, helps men bring up and maintain their sex drive. To further develop their research, the president of the company has hired a succubus. Known for their sexual drive and ability to manipulate male sexuality, the employees imagine a very foxy woman. But when they see that the succubus is Yamashita Madoka, a young innocent looking girl who is just as pure as she looks, they don’t know what to expect. Will Madoka be able to contribute anything to the company even if she is a virgin?

From the Animeraider:

Have you ever read a manga and thought to yourself, "Why the hell did he do that? It's not what I would have done. I could do better!" Well, now here's your chance. This manga changes storyline depending upon choices you, the reader, make. Have fun!

The story follows Erina's route in the Dracu-Riot game. Erina is a foreign vampire from Russia and she is very ecchi, her conversations often involve ecchi stuff which makes Azusa really edgy and Yuuto nervous.

A collection of mildly ecchi otokonoko-styled stories focusing on crossdressing high-school boys and the boys who like them, mostly from the men's magazine Oto Nyan. Some of the stories are continued in Hiriajuu Shuudan ga Classmate o Josousasete Kanojo ni Shite Mita.

1-3. Raising Decoy
A boy helps his classmate go undercover in drag to catch subway gropers, and finds that he looks disturbingly good in a dress....

4. Ato no Matsuri (retitled Spilled Milk in the English edition)
A group of male students, having failed to get girlfriends, are becoming desperate; what will these "innocent" boys resort to?

5. Tenshi no Houbutsusen (Parabola)
Baseball-themed romance short.

6. Actress
A boy joins his high school's film club to meet the actress from their amateur film, but gets a surprise...

7. Shishiza no Boku to Natsu no Yozora (retitled Leo and the Night Sky of Summer in the English edition)
The president of the school astronomy club wants to catch UFOs.. maybe some "sexy female alien" costumes will help?

When Yuko randomly runs into her aloof classmate Arisa one day, she's delighted to get a chance to get to know her! She cheerfully accompanies her to Shibuya, where Arisa says she has an important job that only she can do. As the situation turns violent, Yuko realizes that the mysterious Arisa has a lot more secrets than she could have guessed. Is Arisa involved with the urban legend of the "Execution Girl," who punishes evildoers?

Compilation of short stories:

• Hotel: Since 2079 (2006)
It is the year 2272 A.D.
A computer continues to live on in order to complete a mission in a world where all life, including Mankind, has gone extinct. This is a record of those 27 million years of its heroic struggle.
• Present (2006)
Hanako suffers from a terrible disease. After awakening from a deep slumber, Hanako has only three days to live.
• Subete wa Maguro no Tame datta (It Was All for the Tuna) (2008)
Tuna have become extinct and Jun Shiozaki will do everything possible and imaginable to bring them back.
• Stephanos
Set in modern-day Japan, our main character Noriko finds out that she is pregnant with her lover Matsumura’s baby. He, however, is an important doctor with a family and everything already. Noriko wants to have the baby, but Matsumura says that it’s actually a rapidly growing cancer and that they have to remove it immediately. It might also be neither of these things…
• Diadem
A "Diadem" is a word for 'crown' that has its root in Greek. "Stephanos", which appeared in "Mandala" 01, was also a 'crown'. It seems that we could consider this the second work in a continuing series of shorts that should perhaps be called a "Crown series".

1-7. Colorful Hayate no Gotoku!
8-16. Hayate no Gotoku! Limited
17. Hayate no Gotoku! Dai ?-wa (Hayate no Gotoku! Chapter ?)
18. Hayate no Gotoku! Prototype
19. Hayate no Gotoku! Variety

From Dan of Population GO:

Ooba Asa woke up one morning and became an invisible man. It isn't just him, but various students around school have been gaining superpowers while his little sister has been losing the same powers. Supposedly the student council president is giving out superpowers, Ooba Amime's powers, so Asa, Amime, and the grudge-filled flame girl, Daimon Yaki, form an uneasy alliance to give the mysterious student council president.

Kai was living a peaceful and secluded life with his special martial arts teacher Gankutsuo, until the day he rescued a beautiful girl, Lee Shuurei, who was tumbling down a waterfall. He has no idea what she means when she asks about a "Tenraimon", but Kai is soon drawn into her problems when her pursuers arrive. Meeting her will change the course of Kai's life!

Included in Otoko no Ko Comic Anthology: Zettai Fukujuu-hen.

In order to determine which hot spring is to be the top overall, all of the hot springs within the region enter an unofficial tournament. The tournament is simple battle of capturing the enemy's flag, but the battle itself goes beyond any human measure. It is customary for a female to enter these battles. Carrying their pride and their flag, their only objective is to defeat their opponent. Hence they are commonly called "Fighting Spring Princesses." Kikko, the Fighting Spring Princess of the Aizen Hot Spring Temple, is an eccentric, hot-blooded person who is going to have her debut battle. Sit back and enjoy the story of Kikko's path to becoming queen of all hotsprings!

The main protagonist is an Iga ninja named Saizou, who meets an Izumo priestess and protects her on her short journey to Sanada Yukimura. Sanada Yukimura is a powerful warlord in the Sengoku era. Sanada wants to gather 10 warriors, a party unrivaled in skill and power, to set his still secret plan into action.

Satomi Azusa is a popular teenage gravure idol. She's also a highly talented baseball player, but, as a girl, she can't play on her school's team. Her father happens to be the coach of the team, and he concocts a scheme to allow her to play. His scheme involves Hirayama Keita, Azusa's childhood friend, a teenager of no particular talent. Keita's redeeming feature is that he looks a lot like Azusa. In fact, after putting Keita in a wig and girl's clothes, not even their parents can tell the two of them apart. To help Azusa's (and her father's) dream come true, Keita agrees to trade places with her during the baseball games. Soon "Hirayama Keita" becomes a popular player, and "he" begins to move towards a career in pro baseball. How long can Keita and Azusa keep up the act? What will happen when people find out?

Volume 1 also contains My Sweet Sunday.

The year is 2028, location in New Koshigaya. A young boy, Isurugi Neru, lives in a poor family and is forced to quit school so that he can find his own way in life. Neru on the other hand, only thinks of one thing: to take revenge on Yagami, a classmate, who's especially gifted and has humiliated Neru numerous times.