Miyazawa Yukino has always been the best. The head of her class, perfect athlete, excellent role model student. She always seemed to have a clear idea of what she wanted in life and how to go about it. Her classmates looked up to her with admiration and adoration. But... who would have guessed? Who would have guessed that Miyazawa Yukino, the prize-student, was really perhaps just Yuki-chan, the greedy, self-serving, praise-hungry, lazy goof?

Miyazawa's place as head of the school was finally challenged by Arima Souichirou... intelligent, smart, kind, athletic, charismatic... everything that Miyazawa had pretended to be all her life... he really was. Studying hard and a large amount of proud determination finally won Miyazawa her place once again. And things seemed to go well. Arima-kun has a crush on Miyazawa, she finds. Things could not be going better for Yukino... until Arima-kun happens to be stopping by the Miyazawa household, and is "accidentally" greeted by Miyazawa Yukino... but not the model student, athlete, mature, composed young woman whom he sees each day at school.

And Arima Souichirou then reveals a part of himself which Miyazawa has not yet seen... he blackmails her with her "secret" to make her do his work for him. Yukino realizes that he is only using her... and that the feelings that he had for her had faded. Thinking he only cared for her when she was mature and perfect, she finally refuses to do his work anymore and runs from him.

However, Arima chases her, and tells her that his feelings never changed. He used the blackmail as an excuse to spend time with her, and as he watched her real personality emerge, he realized he had another side to himself as well. Arima and Miyazawa agree to shed their model-student pretenses and live for themselves, the way they want to. This, however, turns out to be more difficult than they might have expected, as more rivals step into the picture.