There are six main characters, 3 men and 3 women. The three women are sisters.
In order to understand this story a little better, I am going to explain a background that is surfaced on the last volume.
There were three young men. They had a plan to build a company and develop it to be the best. Luck was on their side and everything was going well until one of them decided to drop out and create a new company. He did so because he wanted to build a computer company, but the company they built was going to another direction. His business was going well first. But his company eventually went to bankrupt. He visited his two ex-business partners and asked for help. However, he was faced with a dreading fact that they were also developing high-tech market. He eventually committed suicide due to stress from lone collectors. He had a son, Sin Hoo Kang. He was left alone with nothing.
One of the three original business partners, one of them had 3 daughters. But he was killed in a car accident. The last remaining business man who is now a chairman of the largest company in Korea adopted the three daughters and raised them like his own. Sin Hoo Kang found out about this, and decided to revenge them. His father was their partner also. But they never helped him. [Source: JanimeS]

From Daum.net:

Han Ga-Ram can outwit even gangs of swindlers. After all, everything is solved when she transforms back into her unpopular high-school girl mode moments later... Who would suspect a geek with glasses? There is only MONEY on her mind, day and night.

Han Ga-Ram has a twin sister named Yu Ga-Ram, a relationship unknown to both of them. Unlike Han Ga-Ram, Yu Ga-Ram has to bear the bullying acts of her step-sister. The story unfolds when the twins try to escape their fate...

Suyun's parents died when she was little. She is raised by a too-soft "Bro" and a money crazy sister that sends her to part time jobs by screaming each and every day. The only money she is allowed to have and spend is the money she earns; part of the money she earns, that is. So she works 24 hours a day- during morning she works as a student while during night she works as a par-time job girl. But she doesn't think that is enough... That is why she secretly works as "Guardian Angel", one who defeats those who have bullied the weaker. For a price, that is.
(Source: Acacia15)

From Azure:
Nanhee Hong is the second child in the Hong family. She has an older brother, who is the jjang (boss) of his school, and a younger brother, who is a member of the rival school's gang. When Nanhee meets a mysterious student, things begin to get complicated. What will Nanhee do?

What is a sweet, soft-spoken girl (Ha Li Kang) to do when her brothers, having just learned fencing and martial arts, decide to test some moves out on her in order to "tame her" and make her into their "little slave?" She runs to her knightly friend (Te Hu Kang, not related to Ha Li) for protection, of course. However, what happens when, instead of comforting her, he tells her that she is a coward for running away like a puppy who needs constant protection? No, she does not break down and cry like a weak girl. Instead, she resolves to grow stronger. With rigorous training everyday, Ha Li goes from being a scared girl who cries for help to becoming the Jjang (boss of a gang) of the Doberman gang. However, events lead to Ha Li getting in an accident with a truck. Afterwards, she is reborn into the body of a beautiful, but weak, rich girl Aram Han.

At her new school, everyone is surprised at the sudden change they see in Aram, who has gone from a gloomy, good student to a rude, carefree troublemaker. Many people bully her. When Ha Li finds out that it is all due to Sin Uoo Park, the handsome prince and Jjang of the school who detests Aram, she decides to have a duel with him for the position of Jjang. What will happen next is for you to find out in this romantic comedy Korean manhwa.

A plain high school girl, Sun-Nam Bae
She wanted to be free for once in her life, and decided to rebel. But the result of such rebellion.... being a mom?!
"Who the heck are you? Where did a ugly pumpkin like this roll in from? You think I was born a man, just to live with a ugly girl like you?"
Bravely standing her ground against a spoiled young master, Chun-Doong Mah, with her child. Chun-Doong and Sun-Nam's tumultuous diary of raising a child!!

Chae Woon is the manager of ‘Haeoreum.’ She gets retaliated when she receives Bora’s outstretched hands in front of Eun Gyul, who is in bad terms with her since they were little. “If the thing you hate most is my forced kiss, what I hate most are people that step out during my performance.” Is this jealousy or passion for music? (Source: Alice Dreams)

A story of a girl who is searching for the brother who left her when she was 6 years old, promising that he will come back. Now 12 years have passed and he has not yet returned to her...

Source:Loyal Kiss
After an accident die, Ria become angels bring number 5623. She still can not forget things when alive day and night to remember Ban Ji Hwan - the earthly boyfriend. A year passed, that called Ria accidentally Ji Hwan in the e-book birth names those who will die in 100 days. Ria rush pray for the angels to be down for hearing aid Ji Hwan. Ria enters the Hae So, a girl and a bit shy ... boring life, contrary to the character of Ria permanently. How scandalous subject is crazy, fool ... and put pressure bullying from siblings with different fathers So Hae's mother, Ria bites that pass for all to be Ji Hwan. But to find out, then Ji Hwan Left Ria does not recognize...

Every time you sent me one of your fake smile, my fists clench automatically
If I had a gun in my pocket, I would have shot you.
Tied by a secret that keeps him from loving the one he loves, Choi EunJo.
The handsome and much beloved idol Im Sol - no girl can resist his killer smile.
But for Narae, all she feels is disgust.
Bam!!
Where will Narae's Love Bullet fly?
(Source: Loyal Kiss)

From Vampire Knights:
Alice is the heiress to the famed Han Gan clan. She returns to Korea to search for a husband who can then lead the clan, and has her hands full with competitive suitors, each fighting for the coveted position more than for Alice herself. What they don't know, however, is Alice's true motive...

a girl has been accepted into a famous school (usually for rich people who are there from kindergarten) thanks to a scholarship. All her school fees will be paid by her mom's company. But on her first day, the others student are acting very weird...
(Source: Mangafox)

Gyul, the outcast of the entire school, who used to be unable to get away from dangers without Ri Rang's help becomes strong with a sword obtained at an antique shop?!
Hot-tempered, unruly fighter Woo Ri and
my best friend Gyul suddenly seems different?
My heart beats when I see Gyul!!
Without knowing my eyes turned to look at his lips, and I could feel myself blushing.
This is not a disease, is it?
(Source: Loyal Kiss)

From Loyal Kiss:

A beauty at first glance,
the opposite of organized,
Swearing as part of her daily routine,
The so~ hot girl, Jin Eun Jung

Considered a hunk by everyone,
A textbook example of a good student,
The king of organization,
The student council president,
The so~ hot guy, Moon Seo Young

Suddenly one day,
these completely different people
start living under the same roof
and something starts to change!
In a bittersweet way ?


A hot bad-mouthed girl just lost her wallet, determined to get some money, she sees a guy walking down the street, brings a stick and asks him for money, Moon Seo Young, the oh-so hunky goody two-shoes, whose money just got robbed by a girl. how uncool~ but, he has to forget about that since he has much bigger problems cause, Jin Eun Jung, who happens to be that girl, is gonna start living in the same roof as him. woah~ She really is scary. This must be a dream, right?

From HMR:
A fantasy title beginning in 2001, very different from her typical stories and style. Set in Egypt, this has royal intrigue and murder plots. Pretty suspenseful so far.

I am a woman who is tough to anyone who isn’t my type. Whether he be ugly or decent looking it doesn’t matter. My weakness is a beautiful guy! However I haven’t found anyone yet… “Wait for me beautiful guys, I, Choi Mi Ra will find you! (Source: HMR Scans)

Bishie boy that got transfered and visited Ohn Noori, Lee Sun-Uh.
I was surely suprised that my father, who I never met myself, had sent him,
but to say he's one of my fiancée candidates!!!
AND WHAT?
My father is the king of a secret kingdom?
Oh my~ ♥
Then I...am a princess?
With two fiancée candidates, I ended up with a happy headache...
Ahhhh~♥
Who should I pick to make the right choice?
(Source: MangaFox)

When a fancy house is built, the rumors fly. But what is the truth behind the devil and the angel, or the mysterious boy?
(Source: Mangafox.com)