Naja Gurefu, a half-human and half-silverwolf Feral, endures relentless prejudice and discrimination from both humans and full-blooded Ferals due to his mixed heritage. Despite such adversity, he retains a calm and intellectual disposition, frequently employing precise mathematical calculations to anticipate enemy movements while unwaveringly asserting the accuracy of his analyses and strategies, even when flawed. His profound love for his human mother forms a cornerstone of his character, serving as a recurring core motivation. In combat-oriented adaptations, he wields specialized throwing weapons called wind and fire wheels, and certain media grant him a transformation ability for special attacks, though others omit this capability.

Initially aligned with the World Salvation Committee—an organization dedicated to preserving world order—Naja tracks and combats the World Destruction Committee. His role fluctuates across adaptations: he either engages directly in physical confrontations using combat skills or operates solely as a strategist, providing tactical support through calculations and intelligence without fighting. A pivotal shift follows the death of Kyrie Illunis, a key figure tied to world-ending power; Naja grapples with internal conflict over his role in Kyrie’s demise, ultimately joining the protagonists. He aids their mission to resurrect Kyrie and confront higher authorities threatening global stability, contributing indispensable strategic insights during clashes with adversaries like the Beast Lords. His arc navigates ethical dilemmas of world destruction and systemic oppression, yet his loyalty to companions and foundational principles remains unwavering.