The woman opened the bag and discovered a friendly ferret snuggled in with the teddy bears.
RSPCA Animal Collection Officer Kirstie Gillard was summoned to the scene and took the ferret, now dubbed Honey, to a veterinarian to be examined.
"I think the member of the public who found her had quite a shock when her little face poked out between the teddies. Poor honey had obviously wanted to find somewhere nice and warm. We don't know if she was abandoned or if she escaped but she had no microchip and no owner was ever traced," Gillard said.
Honey was found to be underweight, but free of any serious injuries. She was taken to the RSPCA Blackberry Farm Animal Center in Buckinghamshire, where officials said the 2-year-old animal will be available for adoption.