That's by default, anyway. Individual stories need different things.
Ear and tail articulation for sure, including a role in body language and emotional expression. Maybe a touch of temperamental difference by species as well, but subtle and much less important than individual personality. But you still want their society to 'add up to normal', so no huge changes.
A person that isn't what? Good question!
Rather, it seems like despite the way the name implies specificity towards mammals, the word 'furry' itself actually works a bit more like the words 'extraterrestrial' or 'alien'; it defines by exclusion and difference. A furry is someone that isn't.
Or I guess to be more technical, is there a marked difference from baseline human norms that is equally 'different' but in the opposite direction as furries? Some people suggest robots or something, but I don't think the fandom blinks twice at the prospect of a robo-sona.
What's on my mind lately: is it possible to be the opposite of a furry?
Another work for @Wind-Wyrm with their wonderful snek ^.=.^// #art#animalart#furryart#feral#cute#fantasy#art#illustration#clipstudiopaint#furryart#commission#dragon#easterndragon#noodledragon#noodle#eathers#wings#WindWyrm
I have tried and failed to explain the joys of recreational cataloguing to people. It's a remarkably inexplicable game.