On the other side

Aiko is always a cheerful person, all of her classmate love her. When someone ask her how to be happy like her, she just said " just be positive and you be fine". The night on her 15th birthday, she have a dream where she met the other side of her said " I hate you" and she jump off the bridge. The moment the other side of her jump, she would wake up while having a tear drop from her eye. Aiko is trying to find out why the other side of her hate her. While she doing that, she met a lot of struggle that made her hard to keep a smile face. Will she find out the truth? What happend to the other side of her? Will she be able to keep her charming smile? Will she survive?