The 150 square-metre rooftop renovation features gold spheres, velvet cushions and marble surfaces that give an Art Deco feel to the wedge-shaped space.
The combined bar and breakfast area is on the upper floor of the Evripidis hotel in Athen's buzzy Psiri district, with views onto the Acropolis beyond.
A covered terrace area from which guests can enjoy the surrounding view has a tiled terrazzo floor. A glass roof as well as floor-to-ceiling glass windows in this sun room give views across the city.
Circular marble-topped tables are surrounded with velvet-covered dining chairs in soft pastel shades of blue, pink, green and grey. These are accompanied by long banquettes with upholstered velvet seats that line the wall, and smaller tables for pairs of diners, as well as a row of bar stools.
"The vibrant colours in the seating areas were embraced to fade out the neutrality of the grey buildings around the hotel," explained Fluo's interior designer Christina Serrou to Dezeen.
Elsewhere in the bar and seating areas, floors are covered in a geometric pattern of terrazzo and glossy marble slabs that jut into areas of herringbone wood parquet.
A number of the walls are divided diagonally into two triangular forms. These triangular wall panels are decorated with delicate gold filagree laid over bevelled glass that form intricate patterns.
"The metal arches painted in gold make a reference to neoclassical patterns and are a complete antithesis to the sharp edges of the floor," said Serrou.
The gilt accents are complemented with minimal, sculptural lights also in gold, which add to the warmth of the scheme.
Unusually for this sort of project, the designers chose to install a water fountain at the centre of the room where guests can refill their own water bottles.
"The water fountain created in the middle of the space makes reference to the ancient Greek fonts and at the same time it excludes the existence of plastic bottles," explained Serrou.
Ceilings are painted in muted terracotta pink as a reference to the "intense light of the restless sun" in Greece.
Whitewashed walls complement the marble walls in the bathroom stalls and the marble top of the bar in the central triangle, which the designers included as a deliberate nod to local materials.
"Marble that has been perpetually connected with the long history of the city was one of the main architectural materials," said Serrou.
Fluo aren't the only designers to put marble at the heart of their work. Karl Lagerfeld chose white arabescato fantastico and black nero marquina marble for his first collection of sculptural furniture, shown at Carpenter's Workshop Gallery earlier this year.
In New York, Attn Attn Architecture and Design gutted an apartment and used light-toned marble to complement the dark walls.
Photography is by Panos Arvanitakis