Didn't watch the manga and I think I would like it. But I liked this movie.
The pace is good and needed.
The story is about a high school student, Sawako, that as almost zero self-esteem and don't know how to handle it. She met Kazehaya in a crossing and he fells in love for her. He's very popular and he will love her and care for her in secret.
Then, two friends of Kazehaya, Chizuru and Ayane, 2 strong and misfits girls started a friendship relation with Sawako.

The movie tells us the evolution of the four friends, the growing of Sawako's personality and self love, and the realization of true love

It is sweet and warm.
For me, even if it deals with teenage love and high school students, I find almost unreal some behaviour, specially Sawako. But I find sometimes difficult to understand how love relations are portrait in Japanese movies.

I find Japanese women beautiful and strong, but often portrait as submissive and that is very strange for me... Even in a male driven society...