There is a difference between "Sex Education" and "Personal information" I understand you are asking how and what "John" did with his wife. That cross a line.
Remember Amanda Todd? Some info is better to keep it private. Discussing body anatomy is one thing, showing your own breast is another.
Well I guess if MJJ feel uncomfortable to share he won't answer.
But I think LYK probalby is not a good place to talk so "deep" about this kind of thing.
Going to weddingbell forum, or babykingdom type of forum will have more discussion.