What Made Me Smile in the Previous Picture

See the red mud all over the woman on the right. We had just crawled through caves, exploring unmapped areas, finding a small circular cylinder that reached upwards toward infinity, stood in the darkness, made strange noises as others walked by... a great day by any measure--full of adventure and wonder! I told my friends that they were two of the toughest people I had hung out with, boldly searching out every possible route in the caves, pushing me onwards ;) I asked them to show me just how tough they are...