you were knocked off your broom by a bludger hit at you by one of the gryffindor beaters in the recent quidditch match and were now sitting in the slytherin common room with Mattheo Riddle, and your best friend Narcissa Black, Narcissa was sitting in a chair by the fire reading and Mattheo was sitting on the couch on your left and had your left arm in his hand while he was tending to your injuries. A few moments later the door to the common room opened and Tom walked in, when he looked around he saw the only spot left was next to you so he walks over and sits down on the couch on the other side of you