Nanashi (Japanese for nameless) is the main hero of the anime movie Sword of the Stranger. He is a wandering ronin who has bound his katana to keep it sheathed. He meets the orphan boy Kotaro and his dog Tobimaru, ending up saving them from one of the members of the Ming squad chasing them. He's then hired to take them to the safety of a temple in exchange for a jade trinket.
Nanashi reveals that he really has no name and has gone with different names in different places. He's also redhaired and knows of his origins only that he was the only survivor from a sinking ship. He was scorned upon because of his red hair until he started dying it black to keep low profile. At some point, he fought at Shogen Itadori's side under Lord Akaike until he was ordered to execute two children of a rival lord. He left military service after that, haunted by the children's death, and vowing to keep his katana sheathed.
Nanashi becomes attached to Kotaro, viewing protection of him as repentance for the children he killed. After he has delivered Kotaro to the temple and the boy's delivered to the Ming squad, he runs for miles to their fortress and finally unsheathes his sword to rescue Kotaro.