Yoshino, the granddaughter of the local yakuza boss in Osaka, is shocked when she learns that to establish peace between their gangs, she is supposed to become engaged to the grandson of a boss from Tokyo.

The daughter of the president of another subsidiary of the Tokusa group has gone missing, so Yoshino must be accompanied around the clock by Kirishima for her safety.

The semi-criminal group holding grudges against Yoshino and Kirishima, along with Azami Suou, had gathered under Ozu’s command. While Kirishima was with Nao, Yoshino spotted Ozu and his group and decided to carry out a plan on her own. Upon learning about Yoshino’s situation, Kirishima reluctantly contacted Shoma, the only person he could turn to in Osaka, to entrust Nao to him and head toward Yoshino. During this time, Kirishima called Yoshino, and the two made a significant "bet."

Kirishima finds himself in the crowded chaos of a fireworks festival, while Yoshino and a group of delinquents gather nearby. Yoshino chases after Oz, who has been abducted by Naoya, while Kirishima blends into the crowd and launches a surprise attack on the delinquents. Targeted due to the incident involving Shiori Akaza, Yoshino is spotted by Naoya and faces imminent danger. Kirishima continues to take down the delinquents one by one, but a mysterious and dangerous figure, Azami Suo, suddenly appears before him.

"Where is Yoshino Somei?" Azami asks Kirishima. But what is Azami's true objective...?