[quote=@TheWindel]
<Snipped quote by The 42nd Gecko>

Petting Fei will do nothing. Rubbing a knife on her will cause the defense to act.
[/quote]

Considering how deadly some people's bodies are, I would consider an icicle knife far less of a weapon than many people's hands. How does the special dealy know, if not by whether the action will deal damage? It's not intent, because that would have noticed the weapon was not going to hurt.

Is it based on appearances? What looks threatening?