A bit of back story - A couple of weeks ago, a beautiful cat turned up at my back door meowing. I opened my window to chat to him and he tried to jump in so I went outside for a cuddle. This cat hung around for two days, I put a paper collar on him to see if he lived around here but no one called so I took him to the vet to be scanned for a chip and he had one, registered to a town that is at least a half hours drive from here. They called and left a message but no reply, posted a letter to the house and it was returned to sender as the owners had moved. He stayed at the vet for 7 days which, I was told, is the legal amount for rehoming. Lost cat shared all around Facebook, no luck. So I have adopted him.
He is the most affectionate cat I've ever known, he follows me around like a dog, sits on my lap, asks for cuddles. And yet he bites me. I have had cats all my life and made a point to find which areas he likes being stroked and which not, so I know it's not because of that because I don't stroke those bits. He purrs and he's not swishing his tail so I know that he's not being grumpy, I thought maybe affectionate but he has started just randomly biting me on the leg and arm if he's laying on me when I havent touched him, so no idea what to do about that!
This is what I know about him:
He is almost certainly full Siamese according the vet, though I think he is mixed.
He's 2.5
He's neutered
Would love some ideas about why he does this and if I can stop it 