what did mij do to the box

Mij tore the lining of the box in which it was packed in an attempt to escape because it did not find the box comfortable. The box was lined with a metal sheet, and Mij's struggle to get out of the box caused it to hurt itself and start bleeding. The narrator, Maxwell, later found blood trickling from the box and a complete silence from inside, indicating Mij was exhausted and wounded from trying to escape by tearing the box lining to shreds.