I've been a metalhead since I bought Dio's
The Last in Line in 1984. I was 10. So "unknown, but maybe a demon" is pretty rad. I even have one of the pentagram head badges from Crust bikes in the Collection of Cool Bike Crap.
The overall look I see in my head is like this, but also funner and wackier:

But definitely that oh-so-French sky blue metallic, or something similar... there's a factory car paint that's close, I'm sure. And then the "Inconnu" in this font, in a nicely contrasty orange. Kind of a Gulf Le Mans Porsche 917K, at least in inspiration. And now your Phenex will be on the top tube rear. Plus some other things TBDL. I haven't decided on lugs yet, but I'm leaning towards lining in black. (Orange lug lining would be way too much, IMSHO.)
Or maybe a darker blue, with screaming pink lettering to match this:

If only they made it in a 45/28... this 42/26 is tempting enough with the 12-39 9-speed...
--Shannon