Katie Clean invited Messy Missy to her house to work on their group work, but Katie Clean had no idea what a visit from Messy Missy would be like. First of all, it was raining and Messy Missy didn’t take her boots or wipe them on the doormat. Then Messy Missy ate a bag of chips on Katie Clean's white couch, and Messy Missy is a sloppy eater, so chips got all over the couch. Katie Clean tried to be nice and ignore Messy Missy's sloppy behavior, but then Messy Missy threw her chip bag on the floor. Katie Clean said that she was not feeling well and asked Messy Missy to leave. The next day Katie Clean asked the teacher if she could work by herself. After telling the teacher what happened, she allowed Katie to work alone. Messy Missy would have finished her work by herself, but she spilled grape soda all over her papers.
What is the theme of the story?