You asked about the most erotic film I have ever watched 

It was a French movie that I saw when I was quite young 

I cannot remember its title but I think it was called Leonard of the Sun 

It was a French movie typically shot in black and white and was on the lower half of a double bill 

Whilst the main feature was a violent gangster movie 

The support was altogether more subtle 

It did not really have a storyline just moments of expression  

Small theatres 

The man was a bricklayer who sculpted when he could and only took the job so that he could steal materials 

He considered himself to be great artist when in fact he was very limited 

This frustrated him 

The bricklayer called himself 

Isidore Ducasse

The girl in the movie was not given a name 

She was only referred to as She or The Country Girl 

Like the man the girl considered herself to be an artist

 But her work is not seen 

For most of the movie she wears jeans

She is always barefoot 

This I found subtly erotic

 But there is a scene towards the end of the film where she is seen standing at a window

 Wearing nothing but a short tee shirt 

I was not really expecting this to happen and possibly it changed the way that I looked at French Cinema

But it was not the nudity that surprised me but how the scene was conducted 

As the reason that the girl was standing at the window was so she could ask questions about certain landmarks in Paris 

That she is half nude is not important

 It was the natural way this was handled that made it so erotic

 I can still remember it to this day