Our house rabbit, Cheeky, has developed the alarming habit of grooming his owners. He started with James's big curly head. Then he moved onto his eyebrows. Then he started on my head (but he doesn't like it as much because it's a different texture). And now he keeps trying to groom James's beard.
It's not entirely unpleasant. He uses his teeth, but very gently. And when he's finished he flops down next to you as if to say 'my turn now!'.
I'm concerned that he either thinks of himself as a human, or us as enormous rabbits. And that, in rabbit behaviour, grooming is a precursor to mating.