grease

Question
how to remove it from the cat

Answer
Joann,

Without knowing what kind of grease it is, my first inclination would be to use Goop followed by Suave or Pantene Clarifying shampoo and give the cat a bath.  Don't forget to rinse thoroughly and when you think you have rinsed enough, rinse some more.  You will Goop the cat and rinse and then apply the shampoo and rinse.

Best regards... Norm.