The Japanese quilt can keep in heat and moisture, depending on what it is made from. Usually, a futon that includes over 50% hemp or cotton is called a "Menfuton". This is popular all over the world. Futons made from down are called quilt down. This retains heat, so this is a high-class futon. Futons made from feathers are called comforters. This is cheap and is common around the world. Futons made from chemical fibers are called chemical fiber futons. This is cheap so this is popular. Futons made from wool are called "Yomo futon". These are warm.