Poison Ivy II: Lily (1996)

Lily (Alyssa Milano), a sheltered Midwesterner, arrives in Los Angeles to attend art school. In the large apartment she shares with several others, she discovers a diary detailing the sexual misadventures of a girl named Ivy, and decides to transform herself into the girl's image. First, she seduces her housemate Gredin (Johnathon Schaech), and then her married professor, Donald (Xander Berkeley). Lust turns to obsession, which soon gives rise to violence.