Well, you can tell it was a low light room, so clearly from this photo it looks as though flash was used. You shutter speed could have been slower than what your flash fired at. So your flash fired, your friend moved, but your camera wasnt done taking the pic after your flash went off and your friend left the picture. So, the camera recorded yoru friend when the flash went off, and then since he moved, and the cam was still taking the pic it also recorded the wall behind him and meshed the two...
At least thats what could have happend...
I take pics of my friends like that often with my DLSR...haha