[6] Miki was regarded as an early talent and he gained attention along with Hakushū Kitahara, to whom he has been compared in style and stature.

[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.

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).