I once saw a movie when I was a little younger, it was in the start 2000's. What I remember from the movie is an old man, forcing young women to pose naked for him. The man one day grabbed an young girl and she stayed at his home, but one day the girls boyfriend? Friend? Knocks at the mans door and the man opens only wearing a robe. The man then smoothly escapes inside his house but the young man follows and he has a gun. The man wearing the robe runs through the house and ends in a room with a piano. He sits at the piano and starts playing, but is shortly after shot by the young man.

At the end we see the young people, (the man with the gun and the young, captive woman) being married. I don't recall it very much, but the funny part is that I remember that when the man wearing the robe sits at the piano, he throws his robe up and sits, so that his bottom is showing.

Hope that you can help me. That's all I remember.