Right after his birth, he was adopted by Akai Hatsu, a common-law wife of Murō Shinjo, the chief priest at Uho Temple.

This gave him the burden of having double bind thoughts to his biological mother, such as in the following poem, written in 1943 when he was 54 years old: Born into the womb of a hippu (匹婦：a woman in a very low social position who is considered stupid and worthless) on a summer's day.In 1902, he left Kanazawa High Elementary school (equivalent to junior high school today) and started working as a clerk at the Kanazawa Regional Court.

The name was an attempt to compete with Kokubu Saitō, an active kanshi (Chinese poetry) writer in the Kanazawa area at the time.

In 1916, Saisei and Sakutaro started an unofficial magazine called Kanjo (emotions) to publish their work.

He had published the thematically connected stories Yonenjidai (Childhood), Sei ni mezameru koro (lit.

In 1935, he received the Bungei Konwakai (Discussion Group) Award for his novel Ani imōto (Brother and Sister).

For his classic based novel Remenants from the Mayfly's diary (1959), he received the Noma Literary Prize.

The monument features writing authored by Saisei and was designed by architect Yoshirō Taniguchi.

Murō's work has been repeatedly adapted for film by prestigious directors like Mikio Naruse and Tadashi Imai.