This Pet Trainer is an NPC Witch.  She is generated by the cat and dog pet pens.  

It comes with the following files:

2 .iff files  -  Put these files in your GameData/UserData folder or Downloads folder

2 .cmx files
2 .bmp files
2 .skn files  -  Put these files in your GameData/Skins folder

The head mesh is from Frilly Sims.  The body mesh is from Maxis.
