Tilly my bengal (6 ish and spayed at 51/2 months) and Oscar (7ish and neutered at 6 months) they have lived together since she was 14 weeks but have recently been acting a bit oddly - well more her than him really, he will be lying down somewhere and she will go and sit on his head, right on it with legs either side - he is more than a little miffed by this what is she doing, any ideas??????????