"Musashino" by Kunikida Doppo. Compare to Dazai Osamu's work, the language here is more archaic and takes a bit of getting used to, but once you are familiarized with the language, the language itself becomes the most refreshing feature. All stories were written with a style that is attentive to detail, in this slightly archaic language.
Language aside, except for the first story (Musashino), most of the stories collected here are of varying levels of sadness and depression. I thought "Wakare" and "Gen oji" were especially good, but depressing. I still like Dazai Osamu's writing better.
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