The only point of criticism that I have with this game is that Nat is not directly looking or commenting anything when Ethan is masturbating in front of Nat, when she has intercourse with Darrel on the marital bed.
In my opinion it's a missed opportunity to put in one more scene.
As examples:
Nat looks amazed or puzzled at Ethan and ask him what he is doing, he explains that the scene is so hot and that he needs relief.
Or without dialog:
Nat notices Ethan masturbating, they have eye contact, he seems embarrassed at first, then Nat smiles at him and a relieved Ethan smiles back.
Or with Darrel saying something like:
Nat take a look at Ethan, he is stroking himself, I suppose he likes what he sees.
Then Nat and Ethan react promptly, they have eye contact and both look aroused at each other.
Ethan starts to stroke faster and Darrel cpmments about Nat's pussy becoming tighter and squeezing his shaft.