Explicit, yes. However, the character development prevented me from putting these down. You will certainly find yourself skimming over the 'explicit' just to get on with the story to try and understand this couple. It's been a fun read, better if you have a friend to talk to about it because it's hard to explain why it is addictive until you pick it up for yourself.
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"My jaw literally dropped when Cecilia read the secret letter. Then I got to the end & it dropped some more." The Husband's Secret, Liane Moriarty. PInner writes: "Imagine your husband wrote you a letter, to be opened after his death. Imagine, too, that the letter contains his deepest, darkest secret - something so terrible it would destroy not just the life you built together, but the lives of others too. Imagine, then, that you stumble across that letter while your husband is still alive."
See what books were picked by the avid Goodread's folks as their 100 Books You Should Read in Your Lifetime.