"Wot's eh furry?"
Simply put, 'furry' refers to animals drawn (or written about) like people.
People who are "furs", or are into "furries" range from people who collect stuffed animals (or "plushies")
...to people who draw and collect stories and art...
...to people who actually hang around in 'fursuits'...
...and stop short of going back to live in the trees (although there are summer camps for people who like to go live the furry lifestyle for a week!)