I can't believe there are no reviews of this book yet on Amazon. It's a sad state of affair that books like this don't get the limelight they deserve.
At many points this reminded me of Amitav Ghosh's Calcutta Chromosome. Das manages to blend in a thread into Indian history, stretching it all the way from the Mughals to present day Kolkata and the Sunderbans. The story is very allegorical, addressing many questions like sexuality, what it means to be human, the idea of devouring instead of loving, how the former is a forced act and how much it takes for the latter, and how difficult it is.
Make no mistake though, unlike Ghosh's work, the themes here are pretty adult. This is not a fun fantasy book. There is serious stuff dealt with like sexual assault, cannibalism, etc. (Not saying that to deter a reader, but don't make it a gift for a young child without reading.)