Story

＂I'm not a virgin anymore!＂ (But I've only ever done it with a prostitute)
A Special Zone for Structural Reform, the floating city 'Aqua Eden'
The only special island in Japan where things like casinos and the sex industry are now legal.
A student comes to this island with a big goal in mind.　His goal is to ＂graduate from his virginity＂.
His friend, the main character Yuuto Mutsura, has no idea about this outrageous goal, and comes to the floating city to enjoy a simple trip with his friend.

While in the city, Yuuto witnesses a kidnapping!
Unable to ignore it, Yuuto sticks his nose into the kidnapping, and―― gets turned into a ＂vampire＂-!!
As a vampire, Yuuto is unable to return to the mainland, and is forced to live in the floating city.......
However, this is only the start of the story that is about to begin.

At the school, classes are held in the middle of the night, and classmates (※vampires) strut around in the moonlight.
He's excited by the huge, unconventional development that he's never experienced before.

And so, in a floating city where vampires and humans coexist, a bittersweet story of the night begins to unfold――