All I could think of when I read your post was "Butter" without claws. I have a stray that I took in almost 8 months ago, Butter, who my vet has nicknamed "Killer", after viewing the scars on my arms. He bites, but he also has all claws intact and uses them quite often! And he is totally unpredicatable. He will sneak up and attack my legs while I am at my desk, but then 15 minutes later, I might find him sleeping within inches of my feet, or right next to me on the bed or couch. I have learned that I need to calmly pet him a couple of times, and then keep my distance. I always make sure to talk softly and sweetly to him, but never fail to say a big, loud OUCH when he latches on to me. I startle him so that he usually lets go. He is NOT trusting yet. And as Leah mentioned, there is no telling what kind of abuse or neglect he suffered in his early life.

Patience is my only suggestion, and to make sure you isolate him in a comfortable space when visitors come. I am always warning people that Butter isn't quite as affectionate as he seems. But most of his aggression is taken out on me for some reason.

Good luck, and Welcome to Pet Talk.

Logan