Finn is a boy character characterized by a simple and cute design, always wearing a white bear-shaped hat that covers his entire head. His face is round with simple expressions, conveying emotions through only his eyes and mouth. His basic outfit consists of a light blue short-sleeved T-shirt, dark blue shorts, and a green backpack on his back. His legs are depicted as long and thin, and he wears black shoes. As an adventurer, he is often seen carrying a sword or tools, giving him an overall active and lighthearted adventurer aesthetic.

Jake is a yellow dog character characterized by a round and flexible form. His face is expressed very simply, showing emotions through black dot-like eyes and a small mouth. His body has the unique ability to stretch and transform freely like rubber, allowing his arms and legs to lengthen or change shape depending on the situation. He basically doesn't wear any clothes, as his natural body itself is the character's design. His appearance gives off a soft and laid-back vibe overall, making him an impressive character with a simple yet unique silhouette.

Princess Bubblegum is a character with pink skin and long pink hair, characterized by a soft and neat impression. She wears a small gold crown on her head, emphasizing her princess image. Her basic attire is a long bright pink dress, with a relatively simple upper body and a naturally flowing lower half. She sometimes wears gloves, maintaining a clean and elegant style overall. While the overall design is simple, the color palette and silhouette effectively reveal the character's sophisticated and intellectual atmosphere.

Marceline is a character characterized by pale gray skin and long, flowing black hair, possessing a slim and free-spirited silhouette overall. Her eyes are expressed simply but are very expressive, and sharp fangs are slightly visible in her mouth. Her outfit often consists of dark-toned sleeveless tops or crop tops paired with tight pants or leggings, and she wears boots on her feet. A representative element is her red bass guitar, giving her a style characterized by a chic and rebellious atmosphere.