B♭
https://gyazo.com/185e2d92bcb5d6deb8bdb3a939631716
keyCでICN 9
https://noritoism.blog/code_b-flat/
https://youtube.com/shorts/99jq_R113BI?si=OXlL4sbwSWq2GEa8
F
より弾くのが難しい