It is the year 2301. Man has terraformed Mars into a beautiful water planet, and has renamed it "Aqua". Built upon it is Neo-Venezia, an exact replica of old Venice, with beautiful waterways, palaces and plazas. Akari Mizunashi, a 15 year old girl arrives from Man-Home (formerly known as Earth) to become a gondolier trainee at a company called Aria Company.
The company is lead by Alicia Florence, one of the three best gondoliers, also known as the three Water Fairies. Trough hard training, Akari aims to become a Prima herself. Many encounters and mysterious events are sure to follow on this planet of miracles.