His full name is Kagamine Len. He has spiky golden yellow hair and teal blue eyes like Rin. He has his hair in a small ponytail. He wears a sailor-inspired futuristic school uniform, featuring a white sleeveless top with a black sailor collar (accented with yellow stripes), a yellow necktie, and a white, sleeveless open jacket. He wears black shorts with yellow piping, a belt with a triangle pattern, black detached sleeves, and leg warmers. He is a confident, energetic, and slightly mischievous with an often "shota" or sometimes rebellious yet loyal personality. He's Rin's twin brother. He likes bananas and banana milk.

Her full name is Kagamine Rin. She has golden yellow hair and teal eyes like Len. She wears a futuristic, sci-fi take on a school uniform, featuring a white sleeveless top with a black sailor-style collar, yellow ribbon/bow, and a black and yellow musical note emblem. It includes black shorts, a white belt with a yellow-orange triangle pattern, detachable arm warmers, and white boots with yellow trim. She is a highly energetic, cheerful, and mischievous tomboy. She is stubborn and argumentative yet caring, frequently pulling pranks while enjoying gaming and sports. She also has a softer, romantic side. She's Len's twin sister.