Plain and inconspicuous, she was high society's unattractive wallflower. Even so, Marielle was proposed to. Moreover, her fiance is Simeon-sama, the popular knight of the Imperial Guard! Why is he with someone like her? No matter how much she was envied and scorned, Marielle was happy. Well, because his appearance was that of a calm, black-bellied Adonis!

Gian Carlo Bourbon Del Monte, a young member of the mafia, is better known by his nickname "Lucky Dog" due to his incredibly good luck.

Despite knowing that he can escape with just a little effort, Gian decides to take a break from the fast-and-furious lifestyle while being held in a maximum-security prison. But when four young mafia captains are captured and brought to the same prison, the Boss of their syndicate makes a certain request of Gian...

Shiori is an office worker who has been feeling terrible ever since her breakup with her boyfriend. She's been trying to forget him but she found herself unable to move forward just yet and now she urgently needs some healing! That's when a palm-sized high school boy named Akira appeared before her. And he seems to be at a loss about his mysterious condition too.

He's like a small animal and he doesn't give off the vibe of a boy... How great! and that's how they started living together but even though Akira-kun is small, he's still a boy so...!?

From Stiletto Heels:
Kanna Seto lost her childhood friend Haruta in a an accident when she was a freshman in high school. Carrying the emotional pain from that incident throughout her life, Kanna is still wounded as an adult. Will she evet be able to love again? The series is composed of coherent episodes that feature different characters.

Note: Won the 33rd Kodansha Manga Award for Shoujo in 2009.

[from cotton candy scans]

Ririka is a high school girl who lives alone with her father. Despite not having a boyfriend, she always has a blast at school and at home everyday while leading a fulfilling life. Yet one day, she finds an extremely attractive older guy at the apartment’s garbage collection site. It turns out that he’s the salary man that just moved in next door, Hino...?

From MangaHelpers:
Azuraito, an orphan taken in by a group of traveling entertainers, has always been able to see spirits that others can't. When he was four, two traveling doctors, who seemed to have the same ability he had, healed one of their troupe members. They left, but people who seemed to either be them, or be exactly like them, showed up seven years later. This time, they joined the troupe as two entertainers, Rebi and Sando. Rebi and Sando were kind of mysterious, and held themselves a bit away from the rest of the troupe, but Azuraito was determined to get to know them. Through his relationship with them, he hopes to learn much more about his abilities and the supernatural part of the world that they both experience.

"My sweet songbird-- my eternal love--
Don't make such a sad face.
When my little songbird gets sad, it feels like my entire world is raining."

The duke known to many as the grim reaper, "Rowan Peruka".
He, the very person who was about to chop off my head last month, managed to become my husband?!
He took me in not as a second or third wife, but as a first one at that?!!

I'd love it if this was true love, but this is all thanks to a mysterious magic spell. And the magic spell's power's been weakening to boot--!

A marriage with a bipolar(?) husband where your own life is at stake,

From NovelUpdates:

The high school girl Manami who had fallen down the emergency stairs at school had, before she noticed, become a three year old in the world of an Otome Game. What’s more, that little girl was one of the rival characters that appeared in the game; the can’t-take-a-hint-burikko-type-rival daughter of a marquis family. What awaited her at the end was social obliteration. Though she did get a bad feeling about this… Manami decided not to worry! It was a dream after all, so that had nothing to do with her. For now, she’s going to master magic! Hooray!

From Chibi Manga:

Yuu is a plain girl who had a determination to change when entering high school. Falling in love with the hot guy nicknamed as "White Prince", but somehow she's keeping an eye on the super sadist guy nicknamed as "Black Devil" too?!

Ameri has no interest in romance, nope, not at all with silly couples doing silly thing throughout Japan she rather avoid it all together. Yet Ameri does remember when a boy confessed his feelings towards her in middle school, but in all honesty she believed it was nothing but a joke. It's reflection time and maybe romance time? Only Ameri can decide her fate.

Amane Anzu, a high school student, is actively looking for a boyfriend. However, most candidates tend to quickly lose interest when they find out she's actually a real divorcee. And if that's still not enough to drive guys away, the fact she has a daughter usually does the trick.

Hari, a destitute girl, got adopted by Duke Ernst at 7 years old when she lost her mother, as the Ernsts had themselves lost their youngest daughter Arina and sought Hari due to her resemblance to the late girl. Even though she received all kinds of persecution by the three Ernst sons in 20 years of life at the Ernst estate, she could finally escape that blood-and-tear inducing life when she was about to get married.

But what is this?
When I woke up from my sleep, I'm back to that hellish childhood! Is this a dream?!

Hmph. If I can't wake up from this dream,  I'll at least live without too much consideration for others now!

Just like that, Hari decided to go astray. Eugene, the "dutiful son" but cold, Cabel, the roughhousing knucklehead, and Erich, the angelic-looking bully and Arina's twin, all three be damned!

This spin-off of Coffee & Vanilla tells the love story between Akutsu, Fukami's rival CEO, and Natsuki, Risa's best friend. Follow the bittersweet tale of the relationship between two lovers who care about each other very much but refuse to be honest with their own feelings.

The passionate love drama of the 5 high school boys who live in the same house. Original Webtoon: http://webtoon.daum.net/webtoon/view/weeklyboys

Orphans Charlotte and William finally confess their feelings for each other and promised to be together forever. Yet, Charlotte is suddenly killed in a motor accident, leaving William devastated. Death is usually the end of most relationships, but it seems that Will has other plans...

Losing her mother, Saika is taken in by her foster father and 3 brothers. She ends up having to raise a god until it reaches adulthood.

From Aerandria Scans: Evilice and Sin are shadowy but attractive characters who have lived for their collections. Evilice collects items that are cursed, and Sin collects ones that were used for murder. Though they compete for the same items most of the time, they have the opposite feelings towards only one item: an old doll. It is a cursed woman who Evilice loved and ruined, and who Sin is jealous of. With stories of sinister items, their secrets spread!

Lee Soo-young takes notice of Shin Cho-ah at a swimming competition. Despite telling him that she 'hates water', it turns out that there's more than meets the eye… especially when she touches water.

The young pirate captain Doret has one very unusual crew member - Ledalia, left to him as a baby by the previous captain. She was raised among pirates and lived and fought just like one of them, until a strange incident reveals to her that she is of a very different birth. And thus, our heroine starts her great stormy adventure to reclaim her birthright, aided by Doret and the pirate crew.

After reincarnating, I found myself as the Villainess in an Otome game I often played in my past life, the world of “Love☆Magical”?!
Although I reincarnated as the Villainess Isabella…having memories of my past life, if I let the scenario play out as it did in the game, I’d be going down the execution route…?! To free myself from the worst possible ending, my noble battle begins, however…
Is it possible I could fall in love with the non-Love Interest character I loved so much in the past, can I really…?!

Can this overly unusual Villainess rewrite the ruin route awaiting her――