New to Site With a Question

Hi All,
I'm new to this site and want to introduce myself. My name is Annie and I have two cats. Maggie May is 6 yrs. old and Jake is 1+ yrs. old. Both were rescues and are as different as night and day. I joined this site because I have a question that no one has been able to answer and I've never dealt with this issue before. Jake my male cat (Siamese with six toes on his back feet) has been fixed, but when he kneads with his front paws he becomes excited and and wants to mate. He usually tries to grab a hold of my arm and bites. If I push him away, he meows aggressively. I've never had a male cat behave this way before and I don't know how to break him of this behavior. Normally he is the sweetest cat ever. But behaves this way at least once a day. Any ideas or have you seen this behavior before?

I've never seen this behavior, but I do have a suggestion.... when he grabs hold, squirt him w/ a water bottle. or don't allow him access to your arms (i.e. if this happens when sitting on the couch, then shoo your kitty off the couch. he can't grab hold and bite you if he's not on or next to you)

'Humping' is not uncommon in neutered male cats. Give him an old sweater or a towel and when he starts on you, transfer him to his 'hump buddy'. He will soon realize that it is the only acceptable place for him to do this.
Why squirt him for something that gives him pleasure?

climbing on my counters and eating my houseplants also gives my cats "pleasure" but it doesn't mean I'm going to allow it. the OP stated the cat grabs hold and BITES. IMO, that's just poor manners, and wouldn't be tolerated my house. if the cat chose to grab hold and bite a blanket or old slipper, FINE - leave the cat alone - but biting the owner is a squirtable offense in my book.

The one time I used a squirt bottle on my Badger, the look in his eyes when I picked up the bottle did it for me - terror - even before a drop of water had reached him. So I switched to a very loud voice (AND removal) and that seems to have done the trick. Now when he 'gets busy' on an unmade bed, all I have to do is walk into the room and he starts talking (protesting his innocence?) and then stops.
Plus where is that squirt bottle when you need it most? - usually in the next room lol.