While not devoid of emotion -- Shinichi's struggle to maintain his sense of humanity provides plenty of moments for that -- Parasyte is generally far more subdued in sentimentality compared to most manga. A certain incident in volume four that would pass for fodder in other series is detachedly presented and ended, with only a handful of references to it appearing since then. This relative sterility stays near-constant throughout the series.
Until this volume. Hitoshi Iwaaki ratchets up and maintains tension from start to finish in the aftermath of the intricate fight from volume five. All factions involved are moving, and this gradually culminates in the penultimate chapter of this volume. Here Iwaaki grants the sort of climax that has been needed, and gives the spotlight and final word to one of the most compelling and developed villains I have read in manga.
I could talk about the various problems and questions that are raised here, but no justice can be given in just a couple meager paragraphs. Iwaaki has simply created one of the most consistently well-written and ambitious manga available in English. It's a cliché, but you are doing yourself a disservice if you have not checked out Parasyte.
(Oh, and Andrew has to be commended for the translation, particularly the humorous asides.)