I place a fragment of my own personality, such as Nero's love of the color black, Mura having crazy mood swings at various triggers, and both of them being canine-esque in some aspect. They also have something I do not, such as Mura being incredibly social. For most other aspects, I have many other sources, namely a group of friends who have their own ideas, though I tend to use them in tabletop RPGs like Pathfinder. Mura actually has an interesting source for their inspiration. My Pathfinder kitsune named Kimi. The main difference is height, as Kimi is 4'2", via fantasy logic, and looks, acts and thinks like a 12 year old despite being 19. The main social aspect they share is overwhelming positivity hiding a hurricane of emotion. Kimi just has the ability to talk to her dead parents and mess your brain up six ways from Sunday.