If he isn't chatty -- perhaps you are? Maybe you could be made to say things, describe them in detail, use certain phases in public while being forbidden others?

Ever tried interrogation scene? (If you do - set the rules first).

And - simple bondage, perhaps under clothes. Directed change of clothing? Great humiliation device.

I know I am being redundant - but do be careful with mindfucks.
It can be exiling - but also destructive.

Also - it has to be personal ...

Pej.