Soft

I can't think of anything softer than a soft, sleepy Koala this one has had his fill of eucalyptus leaves for the day from the looks of things.
The Koala can sleep for up to 20-22 hours a day, mainly because their diet is solely eucalyptus leaves which contain toxins and are very low in nutrition and high in fibre matters and take a large amount of energy to digest, sleeping for long periods is a strategy for conserving energy.