Heloise is a very intelligent and destructive 14-ish-year-old girl who is one of Jimmy's best friends (she has a big crush on him). She has a mad scientist mind and penchant for chaos. She works for Misery, Inc. as their scientist to make products that cause misery. She is very short and has dirty blonde hair pulled into a ponytail and greyish-blue eyes, a long stitched scar on her forehead that is usually half-covered by her hair and a red robe-like dress that terminates in a curved point.