https://www.hotmovies.com/category/245/Plot-Oriented-Historical/

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Gustave Legaspier, the greatest artist in nineteenth century Europe, has lost his inspiration and his passion. After years of being surrounded by gorgeous, half-dressed models, he finds he is bored by the sultry pouts, perfect bodies and flawless faces, which are unfortunately accompanied by Lackluster, superficial personalities. It takes mysterious and haunting cello music to revive his fading art and the beautiful cellist behind it to awaken his dull heart.

The scenes seem like kinda match your memory, but not perfectly. There is a threesome...there is a scene near some stairs (albeit outdoors.) There is sex in an armchair (but it's a lesbian scene.)

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use the hotmovies search engine, but I had no case.

The movie "elegance" is quite close but it is not, I think it is older than 2006.

It is likely that the staircase scene is a thresome.

And something punctual, is that when he finishes fucking the artist, she spits (I think) cum on the painting he had painted.

For the style seems to be a private, or salieri but review all and there is no case.

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Most likely, the DVD was a compilation of the style "the private life of ..." or something like that. Since after this scene comes the one I'm looking for.

What I am doing now is to follow the nikki scene to see what movies appeared but I see it very complicated.

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