From Nyan-Nyan Rampage:

"The final arc of the story begins...

When Takao Osugi receives the mysterious "Universe of the Four Gods" book from his mentor, Einosuke Okuda, he does everything to keep it away from his young daughter, Suzuno. But when disaster strikes Tokyo, can he still protect her from her fate?

Shortly after the tragic finale of Genbu Kaiden, young Suzuno Osugi's tale as the Priestess of Byakko beings to unfold!"

The series tells the full story of the Priestess of Byakko.

Kabuki Takitsugu is a son from a family of the "Fragrance Way", who has the special ability to smell out human scents. A girl named Hatsune appears before Kabuki while he is making money on school grounds by matchmaking people. But for some reason he can't smell Hatsune's scent.

Story about friendship and truth, with of course, a supernatural box.
Begins in a middle school where a mysterious box appears before some boys

From Viz:
Miaka Yuuki is an ordinary junior-high student who is suddenly whisked away into the world of a book, "The Universe of th Four Gods". There she becomes the priestess of the god Suzaku, and is charged with finding all seven of her Celestial-Warrior protectors.

Yuu Watase Masterpiece Collection Volume 4
Story 1: Suna no Tiara - On their way to Eden, princess Tiara and her subjects are attacked, and only the princess survives. Follow her in her quest for revenge.
Story 2: Hatsuki Triangle: Hodaka Hatsuki takes on the personality and abilities of her old boyfriend everytime she touches a practice sword for the Kendo club. Kunie Kenshi is determined to make her normal once again.
Story 3: 700 Nichi no Blue - Oikawa Masumi tells about her work on a painting titled "Blue Magician" and the man who helped her.

Tanpopo Yamazaki is a girl with a dream of attending a high school in Tokyo. Yet when her dream comes true and the famous Meio High accepts her, all isn't what it seems. Students are sorted only by family connections and wealth, meaning friends are nowhere to be found. Taking matters into her own hands, she starts a gardening club. As the year progresses Tanpopo gains what she's wanted (maybe even more) and one by one, people weave into her life in a way that'll change her life forever...

Asuka, who lived in Hokkaido with her mother, moves to Tokyo to look for her father she has never even met before. When she gets to his house, he is not there, only his children who claim they have never met their father either. Asuka decides to stay with her "brother" and "sister" while she looks for their father. Her two "siblings" are living alone and things sorta complicate when Asuka and her "brother" start to fall for each other...
(Source: MangaUpdates)

Collection of short stories:
1. Shishunki Miman Okotowari Ending - At long last, Yuu Watase brings us the final chapter of the Shinshunki Miman Okotowari series. Manato returns from America, but he doesn't come with the best news for Asuka. This might be the last time he returns to Japan.

2. Couple - Inaho has fallen in love with Takumi, the lead guitarist of a high school band. With hand-made gifts and her strange personality, she gets Takumi to ask her out. But only with a special biwa (a Japanese lute) can their relationship last.

3. Chikyu no Arukikata - Ayuki just got dumped. On the same day, she hurt her ankle during track practice. Later, Ayuki gets trapped on the wrong train to the coast. On this train, she meets Hiroto, a guy who has quit school in search of himself. Ayuki wonders if she should do the same.

Summary from Watase's Sorai:

Basically a really cute short story about being happy with the life you have.

[From ShoujoMagic]:

A special short story that was published in a freebie book put out in Sho-Comi, then added as an extra in the last volume of Zettai Kareshi.

Chima Nagatsu, a high school sophomore, has always been able to see spirits that have died but haven't passed on yet. She also has the power to banish them. One day she gets a job from her uncle asking her to banish the spirits in an all boys school. She reluctantly accepts only to find that one of the spirits, Tsukasa, is a boy whom she admires!

Alice Seno seems like a normal girl in high school. She's a bit shy, she's got a crush on a boy named Kyou, and she's got an older sister who is more popular than she is...pretty normal stuff, until Alice has an encounter with a mysterious and magical rabbit girl that changes the course of her life, and Alice is introduced to the sublime power of the Lotis Words.

Kurahashi Mai is a normal girl who strives to be near her crush, Nimura Hiroki. He's a big fan of Sailor Moon, but is the star of the soccer team and popular. On her 16th Birthday, she is given an electronic notebook fitting for a young girl, that can do tasks like your fortune about your love. One night, she accidentally types "Epotoransu" and a boy called Takuma comes out of the notebook, and who will grant Mai one power for discovering that secret. As the story goes, what'll happen in this story?

-- Manga Updates

Every 30 years, a new princess is chosen from the Hime family to serve the Hayagami. The time has come again, but over these past years, records state not a single female has been born, save for one, the 15-year-old Arata. The only problem is, Arata is actually a male! Forced to disguise himself and take the place of the princess candidate until a formal one can be found, he attends the festival only to witness the current princess, Kokuri-hime, murdered, and his own life is forfeit as well, by the hands of the princess' personal guard, the 12 Shinshou. As he runs for his life, Kannagi of the 12 convinces everyone that Arata is the one who has murdered the princess instead, and now everyone in the Imperial Court is after his head!

(Source: MU)

Aya and her twin brother Aki thought they were going to a celebration of their sixteenth birthday at their grandfather's home, but the funeral-like atmosphere tips them off that something's not right. Their "birthday present" turns out to be a mummified hand--the power of which forces an awakening within Aya, and painful wounds all over Aki's body! Grandfather Mikage announces that Aki will be heir to the Mikage fortune, and Aya must die! But Aya has allies in the athletic cook and martial artist Y?hi, and the attractive, mysterious T?ya. But can even two handsome and resourceful guys save Aya when it's her own power that's out of control?

Yuu Watase's Masterpiece Collection Volume 5 consists of four stories.

1) Mint de Kiss Me -
There is a legend that if you kiss the man you like with a mint candy in your mouth, you can become one with your love. Misono is a rather superstitious girl who decides to test this out on Tohno-sensei, a young teacher she has a crush on. Unfortunately for her, she makes a mistake in the attempt to surprise him and instead kisses her fellow classmate Shindou. Of course this would be the time for the legend to work quite literally as Misono’s spirit enters Shindou’s body.

2) Genseika -
Chiya goes to school with her friends and witnesses one of them die suddenly as a flower bursts out of him. The three friends had been together since elementary school, the death hitting Chiya and Yutaka hard. When other people begin dying from the flowers, they investigate possible reasons for such usual deaths. To her surprise, she finds answers close to home.

3) Furimuke Romance! -
The hero of girls targeted by guys peeking into the locker room, Taka has quite the violent tomboy reputation. But all she wants is for some handsome guy to ask her out. A cheerful street vender, Ryouta gives her a special ring with a heart locket pendent to hold pictures. When two photos are enclosed, romance is in the air.

4) Hang in there Nakago (Part I) -
Involves the scenario where Fushigi Yuugi was actually done by real actors. Unfortunately, Nakago (stage name) is a lot more unconfident than the character he plays. At least his one main fan, an unnamed woman with flowers, is there to support him through his worries.

Higuchi Asuka's mother dies shortly after she tells her teenage daughter who her father is. Only knowing the family name “Sudou”, Asuka goes in search to find her absent father. On her journey, she finds a guy being rather rough with a younger girl. Unable to resist, Asuka steps in by battering the guy with her motorcycle. When she discovers it was a big misunderstanding (Manato was just trying getting his sister Kazusa to go home), she drives them back to their house.
Once there, Asuka finds out that Manato and Kazusa are the Sudou family she's been looking for, but the father isn't there, not to mention their mother also being dead since long ago. With no other leads, Asuka decides to move in as Neesan (the big sister) until their father shows up. Things get tricky when love builds within the complex family relationship....

Zoku Shishunki Miman Okotowari (Sequel)

After being kicked out of her apartment, YuMi must find a place to stay, or she will be forced to return to her home in the sticks! Can she convince YoungHo to to defy conventional boundaries and allow her to stay at his place, at least until she finishes college?