Riku is just a normal high school student, but one day when she gets home she finds out that her grandfather has made her the chairman of a an elite school. At first she isn't very happy but when she meet two very cute guys things just begun to get interesting.
(Source: Anime News Network)

Because she used karate on her leery landlord, Natsume can't find any place to live anymore. While she was sitting by the street, a strange man started striking up a conversation with her. But, because she really didn't have any place to go, Natsume was left with no choice but to...

(Source: M-U)

Nanoka who thought she's an orphan was shocked when her grandfather before dying, told her that she has a brother! She went to the address given and found 2 guys at the doorstep. Which one is actually her brother? The blond haired Aoi or the dark haired Kou?!
(Source: Wataame Shoujo)

Nami has been friends with Ryouku since they were children. But ever since they watched a kiss scene on TV, Ryoku became a ''kissing monster''. After entering middle school, Nami is getting confused wondering what kind of relationship she has with him.

Aoi Spice, starts when young female student Ageha-chan meets popular idol singer Ren in the park where she works. But Ren, overdoing his look-how-evil-I-am mood, manages to handcuff her to him.

And then his dog eats the key.

Now the two of them have to live together until either they find a way to cut the handcuff's chain, or the dog...em...expulses the key. As hours pass, they become attracted to each other. Alas, everything has an end and they manage to get rid of the handcuffs...was that what they really wanted, after all?

*spoiler*
The second volume follows their relationship as they start to go out as a couple, but Ageha finds out she must go to England for two years.

Konatsu was asked by the teacher to deliver the lecture notes the mysterious student Yamada Kei, who hasn't been to school. Miyabi also accompanies Konatsu to Yamada's house only to find out....he's an otaku and he said some rude things to Moa. And then....the three's spring and romance starts soon...?!
(Source: MU)Included one-shot:
Volume 3: Hetayan!! (ヘタヤン!!)

Mano just started a new job, but her first day she meets a demon of a man. And to find out that same man is also her new boss what horrible luck! But is he truly a Demon Boss or is he really kind?

Impossibility:
Yoshida Miake is a charismatic first year high school student that is in love with her best friend whom she had known all of her life. The only problem that occurs is the fact that he has no interest in her whatsoever. Heartbroken, she finds comfort from "Mr. Black" and slowly begins to develop feelings for him. But how would a she develop a relationship with a person that exchanges kisses for lunch?