Shūji Tsushima , known by his pen name Osamu Dazai , was a Japanese novelist and author. A number of his most popular works, such as The Setting Sun (Shayō) and No Longer Human, are considered modern-day classics.

The Setting Sun is a Japanese novel by Osamu Dazai first published in 1947. The story centers on an aristocratic family in decline and crisis during the early years after World War II.