The winner of my Silly Guessing Game is Sayre. She was the first with the right answer that wasn't wishy-washy. "I'm a mom... I see this stuff all the time! Some kind of paper that was left in a pocket and then washed!"
Thanks for the fun answers everyone. A couple of years ago we got a front load washer and dryer. Now, leaving a tissue or other paper in the wash isn't the disaster it use to be. What I liked about this "find", was it was heart shaped!