Autistic Hedgehog

Re: Responding to boundary violations - I've only had to do it once, but I had excellent results with reacting as if I was about to be assaulted: falling to the ground and curling up in a ball to protect my neck and belly. That might get a bit of a bad reaction depending on context, but it's a non-violent option that should get the idea across that whatever the offending person did shouldn't be done again, if only to avoid a scene.