From Tokyopop:

Beings who possess animal-like powers walk among humans in this alternate universe. These mysterious mutants, the +Anima, are shunned by society. Four outcasts in particular--Cooro, a boy with crow-like powers; Husky, a fish-boy; Senri, a bear +Anima; and a girl named Nana, who wields the power of the bat--search for others like themselves while trying to gain acceptance in a world cruel to anyone or anything that is different.

A young girl (Kaburagi Aruto) aspiring to become a shoujo mangaka, much to her chagrin, discovers she is fated to become a renowned hentai manga artist (thanks to a time-traveling robot named G-Maru who is also her biggest fan).

The main character Udagawa Gosuke has received his father's dojo, mainly because his father and older brother were made to commit hara-kiri. He wasn't really supposed to get it simply because he's a second son. But due to the way his pops and brother died, he doesn't have a whole lot of self confidence, so he practices fencing day-by-day at a nearby dojo. However, because the people at that dojo are asses, he soon tries to invent a dojo and a style for people who just enjoy it.

However what really sets this aside from most shounen is that the main male and female characters are actually married. (At age 15 no less!)

The girl Utagawa Shino is the younger sister of his senpai, and is a bit...weird, to say the least. She makes rabbit masks to help bring in a bit of money, although to say that she's obsessed with rabbits would be an understatement. She claims it's because "the rabbits will someday reach the moon." When Gosuke invents his new dojo, he decides to make a style of swordsmanship known as "Rabbit Style Fencing."

Souta Inui is a manager at Megapro talent agency, an agency responsible for turning young, beautiful women into stars. Inui, however, spends his time at the office ogling posters of the idols his agency manages, and has yet to bring in any new talent or take on a single client himself.

When told to go to the streets and scout talent, Inui falls and unwittingly grabs ahold of a devil girl's tail, at the same time asking her to join his talent agency. Now bound by contract, the girl has no choice but to abide by his wish, making it her goal the become the number 1 idol in Japan.

But who is this girl? Why is Inui the only one that can see her tail? Is she really a demon aged many thousands of years? No matter the reason or history, it's now up to Inui to turn this aggressive devil with a (literally) killer voice into the number 1 idol in Japan.

Popular composer Shu Ooka has an older lover, a beautiful bully of a man, Shizuka, who is also his cousin. They enjoy a lovefilled life, together with his son Botan... Except, their neighbour, the popular stage actor Ryujin Takamura is actually on an amorous quest targeting Shizuka! Ryujin has real talent at playing the lead role of a lover. But he has also been Shu's rival since they were students! And now, Shizuka is helping Ryujin out with his housework making Shu's heart burn!

Botan also appears in Emono no Kimochi

From MangaArt:
A Gag manga that could be a bit strange... for sensitive readers.

Despite her family's protests, Aoi Sakuraba decides that she is going to marry Kaoru Hanabishi, her love of eighteen years. Once he realizes that her intentions are genuine - and that she's not just trying to get him to reconcile with his estranged (and domineering) family - he begins to definitely warm up to the idea, too. What obstacles must the two overcome in order to be together?

Collection of oneshots. Very steamy!

1) When violated by the perverted school doctor, Mizuru calls out the name of his best friend Natsura. But it's his best friend, he can't possibly be in love with him...right?! With Natsura being mute and Mizuru not being true to his real feelings, will these best friends have a happy (and smex-filled) ending?

2) Ibuki has known that he is different from other boys since he was 12, but he has been able to keep it a secret. However, his dad's new Italian apprentice (who wants to bathe together!) is about to shatter Ibuki's resolve!

3) Hachiya always felt Hozumi's eyes on him in high school, but never talked to him. Now they meet 8 years later in a gay pub but is it just coincidence? Or destiny?

4) Takashina has an imaginary friend name Michael...an imaginary sex friend that is! But he wishes to fall in love with a real man. Maybe his friend Toriumi could be of assistance?

5) Okabe is an artist who doesn't go out much. The first man he fell in love with is getting married soon, what is this difficult feeling? In comes Akiyo, a gay janitor who touched one of Okabe's sculptures. Can this straightforward and simple man show Okabe the world outside of his easel that he's been longing to see?

6) Our Sin

7) Lovesick Baby

Takayama is gay. While at work he begins to take note of successful and peerless Ishikawa, whom he eyes hungrily. Ishikawa finds out that Takayama is gay when he sees him in a compromising position with a hook-up, but surprisingly he does not out him at work. When a deal of Ishikawa's goes bad, he is infuriated. In a fit of rage, Ishikawa forces himself on Takayama. Takayama decides that he can forgive him for this one-time incident, but can this sordid physical relationship continue?

1) Everything For the Sake of Love
Akira is a kind girl who loves to be with her friends. Because of her high success rate in matchmaking, her friends have given her the title of "Queen of Introductions" (Matchmaking Queen)! But for some reason, Aki-chan can't seem to get a boyfriend for herself...

2) If Someone Like Me Would Do

3) Chocolate Contest

From MangaONE:

This is a story about the Over-thinking pig with his frustrations with love, his suffering, and how he eventually tries to cheer up. Of course, while we watch and laugh at his bitter experience, we simultaneously recognize his circumstance in our own troubled relationships. Only when we can understand how feelings change when in love will we find true happiness.

Nikotama Souhei is transferring to a new school and vows to enjoy a new life, living a lifestyle true to herself. Adopting the name Sara, she, a transgender girl, heads to school in a girls' uniform, ready to grab life by the nads and twist. Sara's no pushover: bright, hyper and kind. She is like nothing anyone at the school has ever encountered, and faces hardships regarding her gender identity. But she also finds the sweet, upstanding classmate Naruse Kaito who finds himself knee-deep in Sara's "Brave New World".

1-3) What is Love?
Kojima, the Vice President of the Student Body, always strives to be on the #1 spot in school. He normally gets along with the carefree Kurata… until one day Kojima snaps and forces Kurata to have sex with him. So starts their S&M relationship or is it love…?

4-6) You are the Worst
Hiroto and Kota's parents suddenly got married and the pair are forced to play nice and be the perfect brothers to each other, but will it really work?

7) Give it All to Love
Kaji talks about his type.

8) X
Another omake.

9) Afterword

From Fantasyshrine:

1-2) Keigo and Gunji are both stubborn and prideful men who didn't realize their mutual love for each other until years later when both ended up in the same hot spring together... with their kids!? Will they come to terms with their feelings for each other?

3) Sweet Honey Drops
Gunkichi and Keita (the kids) are growing up and falling in love.

4) Act.
For Ryouchi it's love at first sight with actor Sou Seiji. Getting a job near his idol is the first step for Ryouchi, but of course, Seiji is not the person Ryouchi thinks he is.

5) Dandy at Dawn
Newspaper writer Tetsuya manages to implode his big city life and has to move back to the country. Waiting for him is neighborhood boy Kyosuke who's gotten much bigger in his absence.

From Central Park Media:
In reality, an ugly duckling could never become a beautiful swan. However, when a short ugly boy makes a wish to be reborn beautiful, his wish is granted and he becomes a gorgeous young man that all the girls fall for. Will being beautiful be everything that he hoped it would be?

With the related titles there's a total of 7 volumes, separated into 3 parts:

I. Agreement of the Glass Shoes (this title),

II. Dolls Music Staff, and

III. White Night Fantasia.

The 3 parts are linked by a pair of marbles with glass shoes embedded in them.

Ageha Shiraishi has been sentenced to death, suspected of murdering her four roommates. In her prison cell as she awaits her execution, she tells her warden, Kyousuke, that she is innocent and that she did not commit murder. Kyousuke does some research, but finds that she is still guilty. Upon his return, he finds his superior tied up and stripped. After setting her free, he finds out that he has been tricked, and it was Ageha in disguise.
Ageha can impersonate anyone to the finest detail, whether it be hair color, habits, or even voice. She becomes the first fugitive of the Talsis Prison and she declares that she will find the real culprit. Kyousuke now only has one clue, which is "the Ageha" (swallowtail butterfly) tattoo on Ageha's back. The chase between the characters involved begins as they move to grasp the truth!

From JShoujo Scans:

Little Rin Fujiwara hated her own face a lot. It was not until her 6th birthday that a make up box she got as a present changes her perspective completely. In front of the mirror, Rin would play with the make up, which becomes like a magic that makes her stronger. Rin believes make up can change both appearance and heart, because it gives the confidence a girl needs.
Years later, Rin attends her first high school year. She decides to help other girls there to become pretty as well, using her make up box. Rin, hidden under the identity of Ageha, a legendary make up stylist, with a help from her classmate Kisaragi, who has to hide his real identity by crossdressing as a woman, is willing to do magic in front of the mirror and change girls “just like when a caterpillar transforms into a butterfly”. How to meet Ageha and have her make you more beautiful? Easy, just write your name and class on the butterfly card and put it on the bullentin board on the 3rd floor. Ageha will come for sure, so what are you waiting for?

From Lovers Dream:

"If you become my wife, I'll grant any wish..." Maybe it wouldn't sound half as crazy if Saeju wasn't told this by a cat (who may or may not be some kind of prince.) But she's desperate for some payback, particularly when her longtime crush blows her off, ice-cold style. But what happens when you invite someone downright... unearthly... into your life? Saeju's about to find out- particularly when one strange cat becomes one strange "brother" she didn't ask for!