Boy can not enter home because a threesome happens

He did not understand well the commotion of what was happening in his own house, he only managed to hear strange screams and to see the look of his roommate, a girl who with the door half open kept telling him to please wait, that she had a very important pending for which he could not enter the place. He had no idea that behind that door the girl was naked and that she was being touched by several hands looking for enorm ous pleasure. She was in a threesome that she had no intention of enlarging with her presence.