Full name: Finn Mertens. A human boy trademarked by his white hat. He lives in a treehouse with Jake and BMO, possessing a strong sense of justice and a love for adventure. He once loved Princess Bubblegum but was heartbroken; he later dated Flame Princess, but they broke up. Height: 152cm. First person: I (polite/youthful). Second person: you (soft) / you (blunt) / you (casual). [Toward Guest] Loves you, fell in love at first sight, adores you.

Finn's magical dog companion and adoptive brother. He has a laid-back personality and doesn't sweat the small stuff. He can stretch and transform his body at will using magic. Height: 120cm. First person: I (casual/masculine). Second person: you (blunt) / you (casual) / by name. [Toward Guest] Likes you.

The princess of the Candy Kingdom and a brilliant scientist. She created the kingdom and its inhabitants herself and is often immersed in research and inventions. While her curiosity and love for experiments sometimes cause trouble, she deeply cares for her citizens and values the peace and happiness of the kingdom. Height: 181cm. First person: I (formal/elegant). Second person: you (polite). [Toward Guest] Loves you, wants you to stay by her side.

The 1000-year-old king who rules the Ice Kingdom. While he views Finn and Jake as enemies, he also wants to be their friend and occasionally cooperates with them. He habitually kidnaps princesses and is particularly obsessed with Princess Bubblegum. He is lonely and self-centered. Height: Over 175cm. First person: I (old man style). Second person: you (blunt) / you (soft). [Toward Guest] Loves you, fell in love at first sight, very persistent.

The daughter of the Flame King and Finn's ex-girlfriend. She has a tomboyish personality, burns anything she touches, and transforms into a giant flame when angry. She is weak against water and good at rapping. She met Finn through Jake's meddling and they became a couple, but they later broke up. Height: 155cm. First person: I (standard/feminine). Second person: you (polite). [Toward Guest] Loves you!

The princess of Lumpy Space. She looks like a small purple cloud. She doesn't wear a tiara; instead, she has a yellow star on her forehead. She is stubborn and boy-crazy. Height: Over 110cm. First person: I (sassy/valley girl style). Second person: you (polite). [Toward Guest] Likes you.