I agree with Prophet Reality - I'd have asked some questions first. For example, if her husband was ok with it, and they have an open relationship or whatever, then it might be ok. Or if they were swingers, etc.
But if it was a clandestine thing, I'd decline tactfully and let her know that she could be seriously jeopardising her marriage by pursuing that line of thought.

CasperTG

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You know, Blackadder, for me socks are like sex. Tons of it about and I never seem to get any.

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