This isn't your 'Chronicles of Narnia' CS Lewis

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This is probably his most mature, honest, and psychologically dense work. Also, I believe his wife had a heavy hand in guiding him with some of it too, so it's one of the better offerings at presenting a more well-rounded depiction of women as well.
The story itself is a reimagining of the Cupid & Psyche story, but from the 'not even a 6 in Greeklands' sister. One would think she's someone we should hate, but she's written in many ways that's painfully relatable. If you've lived a little, and experienced a few things, you'll see the pieces that resonate.
It does a great job at balancing the psychological unpacking with the fantastical elements (imo).