Furoshiki is actually a sub-character in Sumikko Gurashi that was secretly shown when we were introducing Shirokuma.

According to the official introduction, it's described as “Shirokuma's baggage with a pink background and white polka dots.” It's often seen being carried by Shirokuma, laid on the lap like a blanket, or being dragged around.

It's occasionally washed and used to be depicted with a smiling face in many illustrations. However, it has increasingly been drawn with a blank expression after a certain point.
But when it's apparent that Shirokuma hugs or treasures it, you can slightly see the corners of its mouth rise.