This is a Thylacoleo carnifex, or Marsupial Lion. I may come back to this and colour/shade (it's fur colour would be entirely artistic because not much is known about that part...), but the lineart is good on its own.

One of the megafauna that roamed Australia. Read more here:

http://en.wikipedia.org/wiki/Marsupial_Lion


Artist Note: I was vaguely toying with the idea of drawing Kat Aclysm as one of these and it didn't turn out very well... maybe I will have another shot some other time.