I don't think lesbians sniff each others panties. They know the fishy smell firsthand. Her actions do not make sence.
I wrote it before and I'll write it again. Opening to the idea of incest should pass through her interractions with Dylan.
Once the Dylan story is complete with them having sex, at that point she will obvuiously be in a state of opening up to other erotic stuff like lesbianism, interracial etc.
Take the picture below and imagine this:
The next day, after pleasuring Dylan, Sophia's mind is in turmoil. Her feelings are mixed. She goes into the bathroom and looks into the hamper and sees her OWN panties discarded. Suddenly, images of Dylan jerking off to her panties come to her mind. In conjunction with the smell of his sperm all over her body and hand, she craves to smell him again. Now, THAT is HOT as heck. THAT would make total sense as a continuation of the novel.
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