In the year 2010, 18 year old Meiosei Sayonara wakes up in an unfamiliar house with nine strangers. Two mysterious figures tell them that by the end of this experience, only two will remain. Three years later, 20 year old Kauzha Shinobu and her friend Amane find themselves in a similar situation. Using clues from the past and future, both girls try to make it out of the house with as many people alive as possible, which may be more difficult than simply not killing eachother! Or maybe it is that simple. It's up to you. After all, there's two chances to get things right!