I have a three year old Persian, and he is well behaved, playful, if a little aggressive around strangers, lately he gets these fits where he will start biting my arm, at first I thought he was playing so I hid it in my sleeve, he goes crazy, keeps trying to get above my arm and start humping, he gets frustrated every time I try to remove my arm, keeps meowing in agitation, tries to bite or scratch me, even when he calms down my arm has to be in contact with him for a while before he will let me take it back, what does this mean? Does it signify some illness, I have never heard of a cat acting this way!