Nanashi is an Otaku living in the Akihabara district, called Akiba for short. Recently, however, Akiba has been overrun by Synthisters. Synthisters are special vampires who, rather than feast on blood, consumes the social energy of the citizens of Akiba.
Nanashi gets roped into this conflict by being lured in by the offering of rare character items and getting captured. He gets turned into the undead, but only briefly until a purple-haired girl, by the name of Shizuku Tokikaze, saves him. Now these two, along with the unofficial Akiba Freedom Fighters, must fend off the Synthisters and save the citizens of Akiba.
In order to defeat these vampires, though, they must expose them to sunlight. Completely. As in they must completely strip them of their clothing. Only then will they be able to send these violent beings back to the netherrealm and save the humans they have imprisoned.
