Mino Nenki was one of ten ninja selected by his leader Ogen to represent their clan of Iga Tsubagakure against the chosen ten of the rival Koga Manjidani clan.
Nenki's simian features, excessive body hair, and use of a bo staff in combat cause him to bear a strong resemblance to Sun Wukong, the monkey king of Chinese Mythology. His personality is prideful which often makes him underestimate his opponents and leads him to act carelessly in battle. While he defers to the command of Yakushiji Tenzen over that of Princess Oboro, Nenki is comparatively more patient with Oboro's indecision than the majority of the Iga; viewing her infatuation for Gennosuke as a childish phase born out of her sheltered view of the world and believes that as time goes by she'll eventually grow out of it.
Although lethally proficient with his staff, Nenki's greatest weapon is the control he exercises over his own hair. Draping down his back in a tangled mat, Nenki is able to straighten his hair and manipulate it as a grasping tool. His hair is also strong enough to swing him from tree to tree (leaving his hands free for combat) or even to wrap around an enemy and crush them like a Boa Constrictor. Beneath his robes, his body is covered in coarse fur that can be stiffened into needles to skewer any opponent that gets too close and also provides protection from certain techniques. In the manga, Nenki's hair reflects his moods; writhing wildly whenever he becomes enraged or excited.