in a duo with had's samurai, eiichiro fujio! they're enemies who HATE each other (co-workers.)
they were originally inspired by zane from lego ninjago cause i always thought he was awesome. although they're kind of opposites aside from being robot ninja.
kirua is actually a well-known actor in the popular children's series turned media empire 'honors of steel', where they play the primary antagonist, kira kazutame.