The huge cup

Today my grandpa was telling me a story. I don't know if I believed him but it was so good I had to. He said he had seen a huge cup buried underground. He said it was owned by elves. one night he got his friends to do camping. They were amazed, they had never seen anything thing so huge. I told them keep your feet inside the tent other wise the elves would get you. The next morning I checked my feet, they were dripping with blood. mar says it's not true. "But it is", he showed his scared feet.