At one time, Sepang Blue was a popular choice on Audi S and RS models. What was once a standard and sought-after color cycled out, making it more rare.
Not a color combination you would expect or maybe even ask for, it's highly likely the 964-era Porsche 911 Carrera 2 Targa you see here may very well be one of a kind.
This 2017 BMW i8 listed on Bring a Trailer is a Protonic Frozen Yellow edition finished in (you guessed it) Protonic Frozen Yellow with an unspecified interior (bringing a unique visual presence to the platform).
Ipanema Brown is a longtime favorite hue of Audi AG, particularly for their European auto show fleets. That said, browns typically aren't a common go-to for Audi exclusive colors and this was likely a factor in the establishment that this car is a claimed 1-of-1.
When it comes to tailored cars, it's fair to say that Nish Pillai is a bit of a Savant. He's got a fixation on cars from Audi and Porsche, with a specific penchant for Nogaro Blue.