While combing through the belongings of his recently deceased aunt, Matsuko, nephew Sho pieces together the crucial events that sank Matsuko’s life into a despairing tragedy.

In order to settle a business dispute, a mob leader murders one of his own teenage sons. The surviving son vows to avenge his brother’s death, and organizes his own gang of teenage killers to destroy his father’s organization.

Two sets of parents divorce and marry each other, while their children Miki and Yuu are caught in the middle and start falling for each other.