From the introduction:
A world in which humanity has met its end.
A world in which everyone has died.
A world in which nothing more can die.
In which naught stirs but walking corpses.
The protagonists of Nechronica are the girls of this world unfortunate enough to possess hearts - the Dolls. To put it simply, it is a game in which the players become zombie girls and fight against other zombies. The one who caused the dead to wake - the ruler of this shattered world - is the Necromancer. The Necromancer serves as both the master of the game and the archenemy. For it could be none other than the Necromancer who gave hearts to the Dolls. For in a world filled with mindless puppets, the Dolls - they alone whom possess wills of their own - are no more than toys. For the tragic comedy wrought by the foes sent against them is a delightful spectacle. Since Dolls are already dead, they will find no rest when they are broken. The peace of death came to an end long ago, just as did the world itself.
As we have a cup of tea, beneath these skies as gray as lead let us tell the tale of this long, long epilogue.