Vampire's Kiss 1989

Wikipedia: "Vampire's Kiss is a 1989 American dark comedy/psychological horror film. [It] is the story of Peter Loew (Nicolas Cage), a driven yuppie literary agent, who is slowly and inexorably going insane.

Loew plays the consummate businessman by day, and club hops by night, with little in his life of any importance but one night stands and the pursuit of money and prestige.

As the film opens, Loew tells his therapist (Ashley), whom he sees frequently, about his latest sexual conquest. During these sessions at the psychiatrist's office, the viewer is first introduced to Loew's declining mental health through a series of increasingly bizarre rants that eventually begin to scare even his psychiatrist."