Narrator
The unnamed narrator, a well-off young man from the countryside, attends university in Tokyo. Youthful and earnest, he is drawn to Sensei but feels alienated from his family.
Sensei
An enigmatic man who lives a reclusive and idle life with his wife. Although he is weary of the world in general, he becomes a mentor of sorts for the narrator. He hints of his dark past, but never reveals it.
The Narrator's Father
A pleasant and simpleminded old country man who is suffering from kidney disease.
The Narrator's Mother
A kindly and simpleminded country woman.
Sensei's Wife / Ojosan
A very beautiful woman whose seemingly simpleminded nature belies her strong emotional intuition. Sensei calls her by her name, Shizu; but in the context of his story she is called 'Ojosan,' which is the polite form of address for 'young lady' or 'daughter'.
Okusan
Ojosan's mother, a soldier's widow. 'Okusan' is the polite form of address for someone else's wife.
K
The motherless son of a Buddhist priest, K is an extremely idealistic, determined, and indifferent young man who has been Sensei's friend since the two were young.