The Mnemosyne manga adaptation, illustrated by Miss Black, started serialization in the male-oriented manga magazine Comic Valkyrie on May 27, 2008, and is published by Kill Time Communication. 
(Wikipedia)

Before the release of the first anime episode, a light novel adaptation entitled Mnemosyne no Musumetachi 2008 started serialization in Hobby Japan's light novel magazine Charano! on January 30, 2008. The light novel is written by the scriptwriter of the anime, Hiroshi &#332;nogi, and illustrated by Ch&#363;&#333; Higashiguchi. 
(Wikipedia)

Rin Asogi is an immortal private detective with a thirst for vodka and a talent for attracting things that go bump in the night. In a series of nightmarish vignettes spanning sixty-five years, Rin's lush body is sadistically pierced, blown up, and mulched to a bloody pulp. The fiend behind her tortured existence is Apos, an eternal being obsessed with sacrificing Rin to Yggdrasil, the tree of all life. While Rin struggles to unravel the secrets of her endless agony, Apos lurks in the shadows, eager to tear into her ripe body and devour the memories of her countless lives. Rin's no stranger to the realm of the dead, but her next visit could last forever. 
(Source: FUNimation)

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