By Atsuko Asano
Published by YA! Entertainment (Kodansha)
In the middle of a post-apocalyptic desert lie six seemingly utopian cities.
As a child Shion was picked out to become an member of city No. 6's technical caste. Given advanced scientific training, he was on his way to becoming a member of the city's elite. But then one day he discovered an injured rebel named Rat, and decided to help him...
Now considered a traitor by the city, Shion has been expelled from elite society and forced to work as a park attendant. But one day Rat returns and warns Shion of secret experiments taking place in the city's research labs -- experiments that could spell doom for humanity. Together they flee to a settlement in the wastes beyond the city and plot to expose the corrupt government of No.6 for the horrorshow it is.
This is technically a young adult series but not a light novel, though the difference is mainly the lack of illustrations. Shion and Rat are both guys and there's a sexual undercurrent between them, but most fans don't consider the series BL because it's not the focus of the story.
There was an anime back in 2011, but trust me, it's not worth watching. It was on noitaminA, so they only had eleven episodes to adapt nine books, and the parts they ended up cutting were the ones that explained what the hell is going on, so you end up with a show that looks cool but makes no sense.
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