walter 22-year-old grey-headed flying fox bat , from sydney , picked up his taste after sneaking a slurp out of his owner 's cup of tetley 's tea .
the bat has been grounded by the debilitating disease and spends his time lying around in hammocks , sipping on tea and eating .
however , while walter may prefer a mug of tea instead of a mug of blood , he drinks only purpose-made tea .