Sweatshirt

Basically, a few days ago 17 people decided to go off and kill a bunch of school children while they were on a field trip to a factory. The chaperones were gone and the murderers could kill easily. Each one of the murders wore sweatshirts and sweatpants with their number on the inside of the hood; 1-17. One girl saw them coming and hid in the closet. She watched and counted each one as each of her friends was stabbed and shot. She managed to work up the confidence to go to the nearest office, get a knife, and stab and kill the last person who came in; number 17.