Sukeban Deka S1

Undercover cop Saki Asamiya (played by the dangerous-looking and pouty Saito Yuki, below), gets missions from her Controller, Jin, who has a habit of appearing in her bedroom, unannounced!
Though she appears moral and selfless, Saki is being blackmailed by the authorities, on a promise to release her murderous Mom from prison. She gets messages from the ‘Dark Director’ who, like Charlie, talks to her on a speakerphone. Off she goes on missions armed only with a deadly steel yoyo (with a police badge hidden inside).