"Yes, as payment you have to give me oral pleasure", she states matter-of-factly. Figuring there's no other way around of this, you move your tongue towards her vagina and start doing your thing...meanwhile it feels like your tongue is getting bigger but you don't care, all that matters is getting this over with. Fine black fur starts growing on your skin, quickly thickening into a shiny black coat of feline fur. You spread your expanding mouth open further to accomodate for your lengthening teeth, ultimately leaving little more in your mouth than a pair of huge fangs. Your face has now grown entirely into a flat muzzle, whiskers sprouting from the end. A burning sensation in your eyes causes you to close them for a moment, and when you reopen them all colors suddenly seem brighter and sharper...The face changes finish with fuzz growing in your ears, quickly rounding out and moving further up your head.
The fingers on which you have been supporting yourself in this position so far slowly melt together, as do your toes, until your thickened hands have no separate fingers anymore, small black claws growing from the ends and the bottoms becoming more leathery and forming pads. Your heavy breathing now reduced to a low growl, your feel your spine rearranging itself into a quadrupedal position and your legs becoming shorter and thicker. You are now giving oral pleasure to this woman with your feline tongue in a completely quadrupedal position, even though it's hard to keep your balance...the final adjustment to fix this comes in the form of your tailbone extending to almost impossible lengths and immediately being covered in the same black fur as the rest of your body, until you have a reasonably sized panther tail swinging behind you.
"Unnnngh...okay, that's enough", the woman says, "we'll consider the debt paid." You roll over tired, producing a low purring sound at the feeling of the woman digging her fingers through your belly fur. "However, as it seems you won't be going far in a form like this...how do you feel like working for us? Doesn't require much accomodation and the conditions are good." You hop onto the floor and sit on your four paws, pondering this deal...they have a point that you won't be going anywhere like this.