[coupleak]

Since he already made that "innocent" comment about your wife and the other neighbour being topless, why not steer the conversation towards that topic. Maybe share some experiences where she actually has been topless (back yard, beach, hottub). Then there might be a chance he says something like "you're a lucky guy, I wish I could have been there/seen that too". Then your reply could be "well if you're interested, I could show you some pics of her wink wink".