Sister in law

This has gone on for a while now. Sometimes respect is hard, when the other person is not held back and does whatever feels good at the moment.
Here is a recent picture of what is meant by 'going for the moment.'
My sister in law visits us all the time and even likes to come with us if we go shopping for food, or even to deliver a document, she wants to go with us.
She always wears a short skirt, never jeans or pants. Sorry.. a couple of times she wore short pants. But always she takes then off when my wife gets out off the car or sometimes just sits like this.

My sister in law sitting in the back

She knows what she is doing, the more I resist the more she does to distract me. The other day she fingered herself while my wife sat in the front seat. When we arrived at the place to deliver the court documents. She leaned forward and put her finger under my nose. She rubbed her fingers under my face and nose... Sat back and smiled like the devil who just won a soul, barely putting her pants back on a minute before the Mrs. stepped out of the building.
It goes on and on, one time she was talking to my wife about a movie or shopping, don't remember.  Well the thing is she got completely naked while she was talking to my wife was was sitting up front with her hand on my leg. I just held my wife's hand trying desperately to remember where I was driving to. Keeping my eye off the rearview mirror as best as I could.