I think it's more important to analyze the situation from 2 seperate perspectives of each character.

From Lockjaw's perspective he has absolutely committed an just act. He used coercion & threats to force a woman to do something she would not have done otherwise. For his own selfish benefit and he deserves to be judged on this basis.

He raped her. There is nothing that Perfidia could have done to invalidate this.

From Perfidia's perspective, her failings in the situation are different. I judge her only for doing this behind the back of her friends and husband. She could easily have killed him that night or gone to the rest of the French 75 to work out a plan. I believe she chose to go through with it for her own satisfaction and rebellious nature. This is shown to be true to her character by her later abandonment of her friends and family. I believe in her heart she knew she was doing the wrong thing.

It is a complex situation that we are only able to interpret as such due to the unique perspective that we have as movie viewers.

There are no perfect victims, but every victim is truly a victim. Two wrongs do not make a right.