This is the third Haruki Murakami novel I have read. Therefore, I think I may safely posit that "if I can tell you what a Haruki Murakami novel is about then it is not a Haruki Murakami novel."
I came to this conclusion some 200 pages before Tengo's father tells him (I loosely quote) "If you can't understand it without an explanation, then you can't understand it with an explanation".
Mr. Murakami's prose is wonderful. I find his male protagonist's more one-dimensional than than his female protagonist's or other supporting characters. Perhaps because the male protagonsits are on a journey. A journey they do not understand, other than they must not give up.
A final thought on Murakmi novels. I venture Murakami fans say the first Murakami novel they read is the best. While "1Q84" delivered a beautiful, enchanting, mystical, magical, weird, dark, enigmatic and transcendental experience it was NOT my first time through Mr. Murkami's imagination. That belongs to "The Wind-Up Bird Chronicle".
The world from "1Q84" - with two moons, the smaller one, a dohta, to our usual moon, a maza will be with me a long time. But not as long as a simple well, the Japanese occupation of Manchura in WW II or two sisters with very strange powers from "The Wind-Up Bird Chronicle".