[8] Around 1918, he joined Miekichi Suzuki's recently founded children's literature magazine Akai tori (赤い鳥, "Red Bird"), to which he contributed work, participating in the magazine's new movement to create high-quality, beautiful and emotional children's verses and songs, called dōyō.

[9] Three years later he published a collection of verses for children named Shinjushima (真珠島, "Pearl Island"), which included the poem "Akatombo" (赤とんぼ, Akatonbo, "Red Dragonfly"), which Kosaku Yamada set to music in 1927.

[2] A large wall-sized monument to the song, with memorial plaques, stands in Miki's home town, Tatsuno.

[11] From 1916 to 1924 Miki worked in Kamiiso, Hokkaido (modern day Hokuto) in a Trappist monastery as a teacher of literature.

His faith is reflected in the essays Shūdōin seikatsu (修道院生活) and Nihon katorikkukyōshi (日本カトリック教史, History of Catholicism in Japan).