Cosa would see an underutilized hand and either helpfully move it into scratching position or provide it with a toy to throw for her.
She obviously understood that clear communication of needs and desires is essential in any relationship.

I know the internet's odds are impossible, but I wish Glen Phillips (lead singer of Toad the Wet Sprocket) knew how often I thought of his song "Dr. Dresser"

I suspect it's far far more often than he'd ever imagine & I'd like to think he'd find a little delight in that.
(I admittedly wish he knew.)