Rasen Kairou
A 2000 Hentai Visual Novel by age, Rasen Kairou (it can be translated as "Spiral Corridor") is a story about a pornographic site, by the creators of Muv-Luv.
University professor Yuuji Saeki has recently acquired a computer but don't knows how to operate it correctly. One day, he meets Shion Mizushiro, brother of his pupil Aoi. He gives him a note with the address of Aoi's personal website, but Saeki mistypes the address. He ends up stumbling on a adult website called EDEN. Curious, he checks what the site is about and stumbles onto something weird: EDEN's webpage and message board seem to be talking about kidnapping and training girls to be Sex Slaves, complete with a location for a cabin where their supposed last victim is at the moment.
Saeki finds the concept far from believable but investigates a nearby park as it fits the description given by users of the website. Checking abandoned cabins, he discovers to his shock that what the users of EDEN were talking about is very real: he finds an imprisoned schoolgirl who seems willing to have sex with anybody who enters the cabin. The girl offers herself to him and, suddenly overcome with dark urges, Saeki wonders if he should have sex with her or not.
Published by ruf and age.
- Abusive Parents: Kano's father beat up her brothers and her. When an planned arranged marriage for her was dissolved by the groom's family, he decided to rape her.
- The Bad Guy Wins: EDEN achieves exactly what they want in the "Christmas Present" and "Negligence" endings: corrupt Saeki into someone as depraved as them..
- Bittersweet Ending: Ending 1. Both Kano and Aoi are freed by the members of EDEN, but their experiences significantly change them, with Aoi dropping out of college and having a baby of her rapists and Kano becoming a very masochistic Sex Slave to Saeki.
- Cain and Abel: In flashbacks, Ikaruga brings up the possibility that Saeki killed his older brother Koji as a child. Saeki dismisses it, but his memory of the day he died is fuzzy. In ending 5, he finally admits to himself he indeed it.
- The Corrupter: Saeki's mindset clearly changes into a more depraved one as he keeps going to the EDEN's webpage, making the site and its members an involuntary example of this. In route 1, they become a voluntary example; they kidnap Kano and Aoi, send videos of them being raped and tortured to Saeki in order to entice them, then leave them to him, with the girls offering total servitude to Saeki. They clearly want him to become depraved as they are.
- Dude Looks Like a Lady: Shion almost looks like a fac-simile of his older sister.
- Entitled to Have You: Hiroshi tries off-screen to force himself of Kano. She beats him up and apparently screws his arm badly.
- Going Commando: In Aoi's "Christmas Present" ending, Aoi is not wearing panties when Saeki meets her after the work while cooking.
- Happily Married: In Aoi's "Christmas Present" ending, Saeki and Aoi become a very happy couple, at least to outsiders. Saeki describes it more like a relation of master and slave where the slave calls the master "teacher" instead.
- Hopeless Suitor: Hiroshi, a fellow university teacher of Saeki and Kano, tries to hit on her, but she is completely uninterested.
- Hot Teacher: Kano Kusanagi is a university teacher with a pretty face and curvy body.
- Meganekko: Youko is shy, cute, and wears big glasses, fitting the trope to a T.
- Never Found the Body: Saeki's older brother died when they were both child by drowning into a river.
- Noodle Incident: Youko doesn't want to visit her parents during the New Year. The reason behind this is never explained.
- Once More, with Clarity: The girls' sub-stories unlocked after you complete (or replay) certain endings offers their perspective of the story, often giving completely different contexts for their actions.
- Parental Incest: Kano's adoptive father raped her when she was seventeen.
- Perfectly Arranged Marriage: Kano was set up to marry a young man she came to like, but suddenly his father died, and his older, more liberal brother un-made the marriage, averting this trope.
- Refuge in Audacity: As shown by Saeko's initial reaction to the website and later Kano's reaction, the worst people assume about EDEN is that they're a site for people with depraved tastes and are not actually kidnappers and torturers and are at worst role-playing the ideas of doing those things to females they know, and females are voluntary participants, so the police aren't investigating them.
- Sex Slave:
- EDEN is specialized on kidnapping female humans, torture them, and turning them into willing sex outlets.
- Kano's father used her as sex slave after her arranged marriage was dissolved.
- Shameless Fanservice Girl: Shouko wears a dress with a generous cleavage, a skirt and skintight pantyhose, and makes very strong advances on Saeki.
- Star-Crossed Lovers: In route 1, if the player decides to rescue Kano or reject Aoi after she becomes a Sex Slave, they become an example of it as Aoi never even sees Saeki again and engages on a depraved lifestyle, with Saeki starting a romance with Kano or staying single.
- Teacher-Student Romance: Aoi and Saeki develop one during Route 1.
- Unwitting Instigator of Doom: The unnamed clan head that dissolved the idea of Kano marrying his brother had no idea that Kano's adoptive father would use the opportunity to punish her and rape her.