Dark Shadow On The Door

This experience happened a few months ago. Some colleagues and I were doing a medical community service in a little town 3 hours ride from Mexico City. We rented a house where the 4 of us lived for the long-year required social service. All four of us became close and cared for each other. One day, one of us (a female colleague) received a call communicating her that one of her friends had passed away. Therefore, on the following days, the rest of us tried to cheer her up by doing different activities. One evening we decided to have a movie and popcorn night in one of the rooms of the house.

My room, which was in front of the room we were watching the movie at, had its white door open (as usual) and from the spot that my friend and I were in the movie room, we could see the door and the entrance to my room. We turned all the lights off when the movie started. However, in the middle of the movie, I saw in the corner of my eye something moving on the door of my room. When I turned my head to look at it, there it was: A clear, solid black shadow of a man on the surface of the door of my room. It had no volume; it was flat on the door's surface, like anybody's shadow on a wall only that it was so black as if you were too close to the wall to make it that opaque. It was a male figure, tall and "chubby"; it was so well outlined that you could see the shape of his nose while he was calmly walking out of the room. I was not scared; the movie was too entertaining to think that there was something abnormal with seeing such a "normal" shadow on the door. I guess I thought it was the shadow of someone passing by on the street. Nevertheless, just a few seconds later my friend turned to me with a frightened expression asking me "Did you see that?" When I asked her "what, the shadow on my door?" she answered she did not see the shadow going out of MY door but she saw a volumed shadow walking across the door of the room we were staying at. She described the same features on it (male, chubby, tall, and calmly walking). That is when I realized that there was nothing "normal" for a shadow to be walking out my room on the door, for my room was in the second floor in the house and, although we tried to reproduce the same kind of shadow with ourselves we never got to make our shadows as solid as the one I saw unless our bodies were touching the surface of the door. It is worth to mention that the friend, who passed away days before, had lived in the house before we did while he was doing his community service a year before. However, he and all his family, girlfriend and close friends lived in another city.

What was it or who was it? I have read that shadow people usually move across empty spaces, cross walls, are blurry or with red eyes. Is the kind of shadow we saw as frequent to see as the others? What happened?