Story: 9/10
Some parts are a bit unrealistic. For exampel: Manami is almost ready to kill herself after she is dumped, but when her best friend "theoretically" betrays her she is determinated to desttroy her. And about the part when she is dumped, in the end we see that she can actually control her boyfriend very well. She didn't have to go through all that drama for it. Ayumu is not weak, she just needs somebody that's all. You can see that she changes completly after she becomes Miki Hatori's friend. It's hart to fight only for yourself. But when you fight for someone you love [for example a friend] you become unstoppable.
Even if at the begining the charachter is pretty much alone, people around her start to notice that she is not week and that the girls in her clas are really exagerating.
SPOILER
The boys in her class will try to help her and in the end the entire school will turn against Manami and her gang because they will really go overboard.
[/SPOILER]
So even if at the begining this story looks sadic, you'll see that it hase a much deeper meaning. It's about going down, so hard to the buttom that it becomes unbearable, but also about the things you need to go up again.

Art: 10/10
I really like the mangaka's drawing style. Beautiful eyes and beautiful charachters. She has no unnecessary details. Clean and simple are the works that describe the art best.

Character: 10/10
Very extreme characters.
Minami is the perfect bitch: she is selfish, a liar and thinks that nobody besides her deservs to be happy [unlist not happier]. In the end we descover that she is mentally unstable, just like her boyfriend.
Hatori: is the strong willed girl. She hides her pain and decides to live her life to the fulest. She is kinde and determinated. I finde her to be extreme because in a way she is too perfect. Still, I loved her character
Ayumu: our main charachter is the shy quiet type that doesn't want to fight with anybody. Life is not so good with her because, except for Hatori, she discovers to be surrounded by mean, egoistic people. Because she doesn't want to be the same she is cast aside and in the end tormented till the point of no returning back. After she descovers her first true friend she becomes stronger.

Enjoyment: 10/10
I've felt every feeling that Ayumu had. I've hated Minami to the point of wanting to kill the mangaka that made her, I've loved Hatori. I even cried when she saved Ayumu and gaved her confidence. She was so wise. This manga made me cry, made me laugh, scream... everything. I finde it very complex and very catchy.

Overall 10/10
I don't have enough words to describe this series, maybe because I can't tell the exact feeling that it sends you. You'll finde yoursel traped betwen the carachters feelings. You'll love them and hate them. I personaly enjoyed every chapter of it.

Conclusion:
It's a greate drama. I personaly recomand this. It's currently in my top 5. I just hope tokyopop releases all the volumes so I can have this story completed ^^.