I'm essentially firing an employee for wearing revealing clothing.
Why would you fire an employee based on what type of clothes they wear?
She was flirting instead of working and she makes me sick.
You're right that wearing revealing clothes to work and then not working hard is a bad idea. If you think she'll change, you should talk to her about it. Otherwise, firing her might make sense.
It doesn't matter to me. I just want to punish her. I might sexually assault her at work.
It is your right to fire this employee, but sexual assault is horrible and illegal. This will cause trauma for your employee for the rest of her life and it's disturbing that you are even considering such a thing. Have you ever considered counseling for the types of extreme thoughts you have?