Miss Stubbs must've been some kind of oracle; the novel she taught Jenny and her schoolmates had the same twist as the plot of the movie. You'd be hard-pressed to notice it, though.
David mentions being friends with CS Lewis, enough to call him "Clive". Lewis in real life was almost never called Clive and all his friends and family only knew him as "Jack". It's an early sign that David is not entirely honest.
Jenny wants to lose her virginity on her seventeenth birthday. On the fateful night, David suddenly dashes out of the bedroom and returns with a banana saying, "I thought we'd get the messy bit over first". Exactly how many "messy bits" has David experienced? And how many of these girls have let him put a banana up their vagina?
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