How does the nurse feel about the city councilman running for Congress?
A nurse, known only as "Coffy" throughout the entirety of the film, seeks revenge against the people responsible for her younger sister's heroin addiction and the widespread violence that exists in her city. Under the guise of an attractive prostitute willing to do anything for a drug fix, she lures a drug pusher and a mob boss to their residences, killing them. After the killings, Coffy returns to her job at a local hospital operating room.
After her shift, Coffy's police friend Carter offers to drive her home. Carter is a straight-shooting officer who is not willing to bend the law for the mob or the thugs who have been bribing officers at his precinct. Coffy doesn't believe his strong moral resolve until two hooded men break into Carter's house while she's visiting him and beat Carter severely, temporarily crippling him. This enrages Coffy, giving her further provocation to continue her work as a vigilante, killing those responsible for harming Carter and her sister.
Coffy's boyfriend, Howard Brunswick, is a city councilman. Coffy admires Brunswick for his contributions to the community. Brunswick announces his plan to run for Congress, and his purchase of a night club.  Coffy is pleased with these developments.  
Coffy's next targets are a pimp named King George, one of the largest suppliers of prostitutes and illegal drugs in the city, and Mafia boss Arturo Vittroni, a criminal associate of George's.
Coffy questions a former patient of hers, who is a known drug user, to gain insight into the type of woman King George likes and where he keeps his stash of drugs. Coffy shows no sympathy for the drug-addled woman and is abusive to her as she looks for answers.  Coffy is on a mission of revenge and no one will stand in her way.  With the information she gets from the woman, Coffy tracks down George and poses as a Jamaican woman looking to trick for him.
pleased