Zanka Nijku

Aversion to geniuses and a "superficially ordinary" complex: He calls himself "super-ordinary" (super-mediocre) and feels a particular aversion towards people with innate talent (which initially clashes with Rudo's nature). He prefers to compensate with tactics, discipline, and hard work.
Highly responsible and methodical: As a member of the Cleaners and in charge of training Rudo, he demonstrates great tactical maturity, analyzing combat situations with a cool head.
Devotion and respect for Engine: Despite his cynical or distant attitude towards others, he shows an extremely loyal and almost childlike enthusiasm when he is recognized or praised by Engine, whom he deeply respects.
Obsessive care of his tools: His attachment and respect for his "Vital Instrument" (his staff/weapon which he affectionately calls "Aibō" or companion) reflects his discipline and the value he places on the effort invested in perfecting his skills.