Normally, Niko has quite an aggressive personality, but when she takes on her alternate personality she becomes a happy, upbeat character who is always smiling. Her catchphrase is “Nico Nico Nii!” accompanied with a pose. She often thinks a bit highly of herself but despite that, she is also caring.
A common joke in the series is that she’s often ignored by the other members of μ’s at her attempts at being the best idol among them. Niko often gets annoyed with the former student council president, Ayase Eli, for taking away the spotlight from her with her beauty and maturity.
Niko was the Idol Research Club’s president until she graduated. In Episode 10 she is shown to be a very skilled cook despite her saying she has never cooked before. However, she accidentally forgot about her lie when it was dinner time, and ended up cooking for everyone to reveal the truth. Niko is also interested in fashion.