The way he turns his undivided attention to me all of a sudden when I went just one step too far in my teasing. (His undivided attention is as intense and therefore fearsome as everything else about him.)

The way his eyes and voice go from gentle to stone cold within less than a second when I do not follow an order, followed by a very calmly spoken "Now."

The way he seems to know the difference between what I can bear and what not so much better than myself.

He is a magician :-)