A year ago, Akia's sister Masega fell mysteriously ill - and Akia knows that one day, it's going to kill her. The only hope that Akia clings onto is the Sun, ascending each day without fail, and chasing away the darkness that hides in the corners of her existence. But on the morning of the anniversary of Masega's infection, the Sun refuses to rise. Something more ominous than a strange winter disease is at play.... something more powerful than the willpower of the Sun... something that forces Akia to gamble her own life in order to save her sister's.