Annie Inch serves as the primary female companion to the central protagonist, appearing faithfully across adaptations. She actively joins most of his schemes and adventures, offering steadfast loyalty and a willingness to assist, despite occasional unexplained irritability. Her personality aligns with a lawful good moral classification, though she possesses less intellectual sharpness than her best friend. Physically, she consistently sports short, straight black hair. Her attire varies: early comics depict her in a simple yellow or blue dress, while the animated series features a detailed blue sailor-style school uniform. This uniform includes a white collar with three blue stripes, a blue pleated skirt with a back ribbon, white socks, and brown lace-up shoes; summer episodes shift to a short-sleeved blue blouse with puffed sleeves. During live-action segments, she undergoes a significant visual transformation, wearing longer black hair and contemporary outfits consistently incorporating teal, pink, and red elements. Her height remains notably consistent, standing approximately five-sixths the height of her best friend and matching her brother's stature. Family relationships form part of her background. She has a brother named Iggy Inch, and both reside with their parents. Their mother maintains a friendship with the protagonist's mother and frequently experiments with new recipes. Annie is sometimes grouped with other neighborhood girls but maintains her closest bond with the main protagonist.