We have a little girl that has done this since the day we adopted her.
She faithfully washes/grooms my oldest son ("her" boy!) every morning!
She particularly likes his ears but will also groom his neck and even
his arms.  She starts by gently licking and soon is giving little, soft
nips inbetween.  sometimes I am even blessed with such loving attention.
 
Kris
[Posted in FML issue 4818]