Nancy Bobofit is a kleptomaniac mortal girl who attended Yancy Academy. She was Mrs. Dodds' teacher's pet, allowing her to get away with anything, including her bullying and pick pocketing.
Nancy is a girl with curly red hair, orange freckles, which Percy describes "looks like they were sprayed on with liquid Cheetos" and crooked teeth.  She mocks and teases classmates she considers weaker than her, and throws food at them to humiliate them for her amusement.