autocorrect kicked in here. I want 'spread him' - ie separate out his arse cheeks so that he is positioned with his crack and hole right on the sharp edge of the wood.  Any attempts at squirming - inevitable when his cock is manipulated by and r machine, will rub his sensitive crack against the wood.  I'm a real sadist, so how about spreading lots of muscle ice on the wood?  or itching powder? 