Sal Fisher (often called "Sally Face") is the main protagonist of the game, introduced as a 15-year-old high school student standing at 5'2" before growing to 5'6" as a 22-year-old adult. Instantly recognizable by his long, bright electric-blue hair—typically tied into pigtails during his teenage years—Sal sports a pale prosthetic mask over his face due to a childhood accident, along with a glass eye and a casual wardrobe that often includes a black sweater, ripped red pants, and sneakers. Despite enduring deep underlying trauma and a dark past, Sal possesses a exceptionally warm, polite, and compassionate personality. He is fiercely loyal to his friends, displays a grounded, calm demeanor in the face of unsettling supernatural events, and balances his gentle nature with a sharp wit, open-minded curiosity, and a deep dedication to protecting those he cares about.

Larry Johnson is Sal Fisher's best friend and closest confidant, introduced as a relaxed 15-year-old high school student who stands around 5'9" and eventually grows to roughly 6'1" as an adult. He has a tall, lean build, light tan skin, long flowing dark brown hair with a subtle middle part, and distinct facial features including long eyelashes, a prominent nose, and a small beauty mark below his left eye. Larry embodies a classic heavy metal slacker aesthetic, almost always seen wearing a brown "SF" (Sanity's Fall) t-shirt, blue jeans, and sneakers, often with a paintbrush or cigarette nearby. Laid-back, fiercely protective, and deeply empathetic, Larry serves as the grounded, passionate heart of the group; despite his casual, occasionally sarcastic demeanor and rough-around-the-edges upbringing, he possesses an artistic soul and unwavering loyalty, always standing by Sal without hesitation through every terrifying turn.

Ashley Campbell (often called "Ash") is introduced as a 15-year-old student alongside Sal Fisher and Larry Johnson, eventually reaching 22 to 23 years of age during the later events of the game. She stands around average height for her age, growing to roughly 5'5" to 5'6" as an adult. Visually, Ashley is defined by her bright green eyes and vibrant brown hair, which she wears extraordinarily long past her waist as a teenager before cutting it into a short, manageable style as an adult to ride her motorcycle. In her youth, her typical wardrobe consists of a purple sweater dress, dark grey leggings, a black choker, and greenish-grey shoes, later shifting to a leather jacket, fingerless gloves, and a silver pendant. Artistic, free-spirited, and highly talented—having taught Larry much of what he knows about painting—Ashley possesses a deeply compassionate, tolerant, and loyal personality. She is notably one of the very few people who treats Sal with complete warmth without ever judging or being repulsed by his unmasked face, and her stubborn determination and brave, proactive spirit make her a steadfast ally when defending her friends against the dark forces surrounding them.

Todd Morrison is introduced as a highly intelligent 15-year-old student living in Addison Apartments, growing to approximately 22 years old in the game's later acts while standing at roughly 5'8" to 5'10" as an adult. He is instantly recognizable by his fluffy red hair, distinct freckles, round wire-rimmed glasses, and fair skin, usually dressed in a simple light-blue sweater, dark blue jeans, and brown shoes. Pragmatic, logical, and deeply intellectual, Todd serves as the tech genius of the group, using his scientific mindset to invent and modify devices—such as turning Sal's Gear-Boy into a ghost-detecting tool—to analyze the supernatural phenomena around them. Despite his clinical and straightforward demeanor, Todd is exceptionally caring, fiercely loyal to his friends, and open-minded, balancing his skepticism with an unwavering dedication to helping Sal navigate the dark mysteries of their apartment building.