My mom's Siamese cat is a very sweet affectionate cat--usually. He has never bit me but he bites my mother enough to break the skin and it happens quite often. Usually he just gets on the bed and tears into mom for no apparent reason. He does bite sometimes while mom is petting him and I think he gets over stimulated (from what I've read). He can be unpredictable. And my mother sometimes makes little fluttery motions with her fingers around him or goes to pet him and then pulls her hand back and I think he feels he's being teased. I'm very careful not to do anything that would make him feel teased or try to pet him for very long. Mom will sometimes goof around with him like pulling loose hair off him or....wait a minute I might have answered my own question! I would bite her too!!
Also if she touches him in different room from what he is used to. Or if she's on the telephone. (Attention getting behavior?)
The only thing he has done to me is stuck my with his nail. If he's settled down to sleep for the night and I try to pet him he will do that. It's a house rule NEVER PET SAMMY AFTER MIDNIGHT.
Who can possibly know what is in the mind of a Siamese? Or my mom for that matter. He can be the sweetest cat in the world and turn into something outright evil in a second.
But is there anything we can do? I love him too much to ever give him away. I might be persuaded to give my mom to a good family-- preferably without pets.