Managed to finish this book in one sitting but I guess with its short length that’s not really impressive lol.
The first half was pretty average and didn’t stand out, but the second half of the book blew me away with its emotional tale.
I loved the mythology aspects and reading from the whales perspective was definitely interesting, but it did get pretty repetitive, especially in the first half. Koro being sexist, whale pov, koro being sexist, whale pov, and then there’s a part of the book where the narrator leaves to Australia? 
Thankfully, once the narrator returns, the book picks up a lot. Around halfway through is when Kahu is older and actually becomes a main part of the story, and the change does the book wonders. The second half is just magical and very effective, there was even a part that made me tear up a bit.
Would recommend.