Absolutely

Why wouldn't you? You didn't transform her into a feline because you found cats ugly. Even better Doe seems to have total amnesia - you can tell her whatever you want. No one is going to disturb you in your sanctum, so there is no one to contradict anything you tell her. You're so powerful that if you did create a whole new race even the king would be unable to stop you.

When you feel her tail flicking back and forth between your knees you know she's about to cum. As her pussy begins to spasm you thrust deep inside her and inject your seed. She lets out an inhumanly deep purr that you don't hear so much as feel. Then Doe's head rolls to one side and she falls asleep. Well, you suppose being transformed into another species could be quite tiring. You decide to have some food shipped in from the kitchens. Less than half an hour later she awakens. You suspect the smell from the tray of luncheon meats brought her around.

You offer her the plate "Eat up Doe, you must be famished after the healing you've been through." She grabs it and starts tearing the meat apart with both her claws and sharp teeth. You make a mental note not to surprise her while your tongue, or anything else important to you, is in her mouth.

As she works her way across the plate she asks you "Doe? Is that my name?" You nod and she smiles, saying "Yes, Doe. It sounds right. OK, hmmm... what else should I ask? I have so many question. Ah, where am I from? Why do we look so different? Are there any others from my home here? That last thing we did, before I fell asleep - can we do that again?"

The amnesia seems to be as strong as before, very handy. "Well Doe there is some bad news, I'm afraid. Your village is far to the north and very few of your people made it here. They hoped I would find a cure, and I have, but you might be the only one who survived because you were young and strong."

Doe looks crestfallen and asks "There's nobody else from my village here?" You shake your head. "I... I don't even know if I have any family. Or... had any family..."

This is a problem. Doe is beautiful and the best lover you've had in a while. Just an hour ago she was a **** and an enemy. You weren't even a hundred percent sure the transformation would work. Now, with the amnesia - not to mention the sex, things are different. If you're really going to try fathering a race of catgirls you might as well think big. There are a lot of enemy slaves for sale right now and no one cares very much what happens to them. If your transformation spell causes amnesia reliably you have a real opportunity.

You could curry a lot of favor with merchants, nobles and other sorcerers if you gave them catgirls as gifts. You could tell them you discovered these feline creatures on an expedition in the north. Claim the war interrupted your efforts to bring some of them south. You're sure most would appreciate the novelty, and those that didn't would probably appreciate the sex. You could create a little harem for yourself, with Doe helping to 'educate' the newly cured catgirls.

You only snap out of it when you hear Doe sniffle. You pat her shoulder "I know it's terrible Doe but there is hope. Your village and others like it split up, hoping the disease wouldn't spread. Another group may show up here sooner or later and now I have a cure ready and waiting." Doe keeps crying but gives you a big hug. As her fuzzy cheek rubs against yours she thanks you for all you've done.