Although we believe that people learn best by doing, a little background reading can reinforce learning. These great books listed here bring in real life examples.
This book will be of use to you if your aim is one day to surpass your sensei. The story about the four horses is important for change agents - the willing horse is a powerful ally but don't neglect the ones who require hard training. 
An excellent read that gives good pointers for managing change. 
As useful for your life as it is for lean. Chapters include: "process not product", "Even the masters have masters" and "Know your limits".
It all makes sense when you absorb his words. More accessible than Shingo's study which wasn't sexy but had teeth
Want to learn how to use data to find out interesting things? The rogue economist who wrote this book has made some fascinating connections
Seven Chapters and not a wasted word. Of Particular interest is a chapter on interdependence of the Sempai - Kohai relationship.
A very good sense check on the behaviours you currently use and those that may be more useful.
Lean tools are of no use if you can't persuade people to try and practice them. You can only do this if you have an understanding of the different ways that different people experience the world.