How old is your boy? Sounds like he definitely is marking, and becoming territorial. The yellow is the buckgrease which is natural, but if it becomes too much you can gently wash just his back with Dawn dish soap...I also use Aveeno lotion (no menthol) on my nakies to keep their skin from drying out.
IF your boy is acting funny, do not let him mount your hand or arm and start scratching at you...this can lead into a frenzy of biting. With intact boys acting like this, I just don't let them do it...if they hug onto your arm (not trying to get up) remove them quickly.
IF your boy is acting funny, do not let him mount your hand or arm and start scratching at you...this can lead into a frenzy of biting. With intact boys acting like this, I just don't let them do it...if they hug onto your arm (not trying to get up) remove them quickly.