The joke's on you, girl.
Karma is a you-know-what, and it's very satisfying to see that play out in front of your eyes sometimes. This girl thought she was being clever, ruining a cute picture for her friend. Instead, her plan completely backfired since she didn't take into account how shadows work.
Hopefully, these two both got a good laugh when they saw this picture (especially the innocent one who thought she was taking a regular picture with a friend).
