Set in 2022, technology has advanced to the point where the human nervous system can be seamlessly integrated into external networks thanks to nanomachines. People leave their bodies behind in water tanks while traversing through cyberspace. However, a crisis known as "Early Rapture" occurs where the system becomes overloaded, resulting in thousands of consciousnesses being lost in the network. Remu Mikage's sister Shiki is one of them, and in an attempt to look for her he visits her apartment. He encounters Shiki there, who informs him that the person he is speaking to isn't his sister, and has somehow taken over her body.
Taito has been really sleepy lately, and keeps dreaming of a female vampire who says she has given him her "poison." Sometimes he even thinks he hears her voice when he's awake. But after surviving an accident that should have killed him, Taito's world changes drastically and he realizes that his dreams are more real than he thought.
Kasugano Haruka and his sister Sora have lost both their parents in an accident, and with them all their support. They decide to move out of the city to the rural town where they once spent summers with their late grandfather. At first everything seems familiar and peaceful, but changes come as Haruka starts to remember things from his youth.
Kate is the voluptuous, virginal new recruit for the Federal Space Army Security Police. Although she's the newest detective in the galaxy police force, she's eager to prove her worth as an undercover agent. Her first assignment is to track down the villains who have been snatching up and raping all the young women of the hot desert planet, Doune. Will she become their next victim? Can she keep her virtue intact while infiltrating their den of ill repute? No mission is too dangerous, no disguise too skimpy, no sexual exploitation too deviant, for our girl Kate to handle!
Note: This anime was originally released by All Products/Beam Entertainment and it didn't feature any explicit sexual content. In 1999, Five Ways re-released an edited version of Nessa no Wakusei with added explicit sexual content. R1 distributors Kitty/Media Blasters released the Five Ways version.
