The story takes place in a floating garden in the sky. Welcome to the well-known and prosperous utopia, the city of Itehari.

The protagonist is Hinagiku, a noble from a distinguished family who longs for the world beyond the floating city.

One day, Hinagiku, who has just turned 18, meets a man with amnesia named Yashiro.

This chance encounter becomes the catalyst that draws Hinagiku into a series of events involving secrets and various truths beneath the surface of the utopia.

Experience this story through the eyes of a noble who was born and raised in Itehari. He meets a variety of characters and forms significant bonds.

Ultimately, lean your head forward into the sea of secrets that lie far, far below the calm facade of the city of Itehari...

• A love story from the beautiful and fleeting world of floating mechanical utopia.
• In Itehari, the well-known and prosperous floating city, Hinagiku desires to explore the world beyond its borders.
• This city in the sky is an illusion of utopia.