This awesome girl is a Casacorn (a cat/dragon hybrid) created by  Nastacula She even has a backstory for them:
"A very rare creature to catch sight of, Casacorns are extremely shy and will fly away at the hunt of danger or loud noises. They are attracted to strong, sweet scents such as flowers, candy, pastries, jam, honey, etc. You can usually find them in the early spring frolicing in open fields with tall grass. When they fly, they literally 'swim' in the air, using their long tails like a rudder, twirling and flipping around.

Usually they are extremely small - the size of a mouse - but some say they have seen them as big as cats...but since the Casacorn's face resembles a cat anyway it's hard to tell if these sightings are true or false.

Their diet is strictly vegetarian, mostly consisting of nectar and green vegetation. They will gradually change color according to their diet and the natural dyes found in flowers. "

However, with Arbor (and Neesh) they are an even rarer breed of Casacorn. Arbor can change her form from cute and innocent to a much larger than normal (size of a large dog) form and is actually an omnivore. This type of Casacorn is typically killed by the rest of their kind to maintain peace in the group. It seems that these two managed to elude their kind's culling.

In contrast to Neesh, Arbor prefers to live off mostly plants and small animals. She also kills them instantly instead of torturing them like Neesh does. She would never harm an intelligent creature like a human child, whereas this is what Neesh loves to hunt for.

Arbor and Neesh have a difficult history with each other. They hatched at the same time in an abandoned Casacorn nest and grew together for the first few years of their life. However, when their bodies started hungering for meat they noticed a severe difference in tastes.