
昔の日本の冬の風物詩からきています。家庭にかまどや囲炉裏があった時代、人が寝静まり火が消えた後、暖を求めて猫がかまどの灰の中にもぐりこんで暖をとっていました。このように灰まみれになった猫は「竈猫(かまどねこ)」とも呼ばれ、当時の冬の季語にもなっていたほど親しまれていた光景
This comes from a traditional Japanese winter scene. In the era when homes had hearths and irori (sunken hearths), after people had gone to sleep and the fire had died down, cats would burrow into the ashes of the hearth to keep warm. Cats that got covered in ashes in this way were also called "kamadoneko" (hearth cats), and this scene was so familiar that it became a winter kigo (seasonal word) of the time.