Testimony began Monday in the trial of a woman who has been charged with murder for allegedly stabbing and killing her lover with a stiletto heel.

The Associated Press reported that prosecutors told jurors that Ana Trujillo attacked her boyfriend in a fit of rage. They said that she allegedly sat on Alf Stefan Andersson after knocking him down and then stabbed him to death with the stiletto heel of her shoe, striking him at least 25 times in his face.

The alleged murder weapon was shown Tuesday in court for the first time. The navy blue 5 1/2-inch heel was found beside the victim’s body on June 9.

Trujillo’s lawyers said that their client actually acted in self-defense because Andersson attacked her after a night of drinking. But the Houston Chronicle noted that prosecutors countered that and said that the 45-year-old was the aggressor in her relationship with the 59-year-old college professor.

If convicted, Trujillo faces life in prison. The trial is expected end next week.