The sweet-looking high school girl Kudo Sayaka (played by Kasumi Arimura) is not liked by her father at home. Her father is determined to train her younger brother to be a baseball player, but neglects to care for his daughters. Sayaka's high school has an internal promotion system, so she eats, drinks and has fun with her sisters all day long, and she doesn't care that her studies have fallen to the bottom of the grade. The gentle and hardworking mother (played by Yoshida Yang) is often preached by the school. She is very anxious about her daughter's future, so she sent Sayaka to the cram school run by Pingtian (played by Atsushi Ito). After the level test, Sayaka is actually only at the fourth grade level of elementary school, but the cheerful and confident Pingtian doesn't care. He opens the girl's defense in a unique way, and the two soon become good friends. With the help of Pingtian, Sayaka's attitude towards learning gradually becomes stronger, and later she set the ambition to be admitted to Keio University. This is the true story of the ugly duckling's counterattack... The film is adapted from "The Story of a Hot Girl Ranked Last in Her Grade Who Increased Her Deviation Value by More Than 40 Points in One Year and Was Enrolled in Keio University", which is based on a true story and was written by Nobuki Tsubota, a private school teacher who served as the prototype of the film's heroine Sayaka Kobayashi.