Both of those works were published in the collection Ten Nights' Dreams.
This author's stories include a one centered on a dying woman who beseeches the narrator to dig her grave with a "large pearl oyster shell," as well as a tale about a father trying to abandon his child in a forest.  Both of those works were published in the collection Ten Nights' Dreams. An unemployed man goes to visit a hospitalized man to blackmail him in the novel Light and Darkness. In another work, a student befriends a Sensei, who reveals a love triangle that featured his best friend K and his landlady.  Another novel contains the characters "Porcupine" and "Redshirt" and the protagonist's times as a teacher in Matsuyama.  His major work features a nameless narrator who leaves behind the alley life and is adopted by the family of a man with digestive difficulties, whom he dubs Mr. Sneeze. For 10 points, identify this Japanese author of the aforementioned works Kokoro, Botchan, and I Am a Cat?
This author's stories include a one centered on a dying woman who beseeches the narrator to dig her grave with a "large pearl oyster shell," as well as a tale about a father trying to abandon his child in a forest.  
Natsume Soseki