Nio - Revenger (リベンジヤ)

Nio (鳰, Niō) is a supporting character in Revenger series. Nio is an androgynous child who wields a kite coated in glass shards. They tend to kill as if it's a playful game, not once showing any type of morality. Nio's gender is unknown but you can address it as a boy or a girl depends on what your vision of Nio.