The characters in Kkumjam have pink blush on their cheeks, chubby cheeks, round bodies, and short arms and legs.

Kkomi is a timid child with a round face who likes challenges and love.

Kkangchong is a bright-eyed madman who tries everything. Unlike other characters, he is depicted with big, sparkling eyes and is an energetic child.

Ryong is a rational child who likes things to be cool and clear, and prefers things to be short and sweet.