Yakuza's Lady 6.

Maki, the female bar manager, has a dark side as a "yakuza woman" who supports Tetsuya of the Uradora clan of the Kanto region. Maki's true identity is accidentally revealed to Natsumi, who works at the bar, and Natsumi's boyfriend Junichi, who has a crush on Tetsuya. Natsumi reports the incident, and the Uratora-gumi is temporarily on the verge of dissolution...