Carl Kimlinger writes:
If you hate Hachi with the heat of a thousand suns, the second half of NANA will only stoke the inferno. In twenty-plus episodes it maps out, in ugly and exacting detail, the evolution of a course of action that would by most standards be unforgivably mercenary. Hachi is the main player and it culminates in a decision that could, if you were kindly disposed, be called self-serving. It's a chain of events that seems almost tailor-made to turn Hachi-haters away from the series.