He looked up, giving her a regretful smile. "I... prefer to be underestimated. It's an old habit. I don't like to frighten or upset people."

Unspoken, he left the implication of how frightened or upset people often acted, like the way frightened people tended to lash out at what had scared them.

And really, it was better strategy to let one's opponents think you weak.

"It has always been better to be thought of as weak and treated with... disdain and bullying than to be thought powerful and attacked for it. And here, I'm incapable of defending myself with anything stronger than my wits. I was... worried. I should have thought better of you, after all the kindness you've shown me. I do not wish to make excuses for my unworthiness as a friend, but..." He sighed. "I was betrayed by everyone I had trusted. It makes me cling to my secrets that much harder."