A gorgeous picture by  foufi of my assassin coalmarten practicing with her shiruken.

She's a fanciful subspecies of yellow throated marten with traditionally-coloured underfur, but melanistic guard fur which obscures the underfur colours unless something like clothing or the wind spreads the guard fur and reveals the colours beneath. Supposedly the flashes of colour put folks in mind of embers or fire, hence 'embermart' or 'coalmarten' (or possibly 'firemarten').

I was trying to think up a made-up species, and conflated the bird species 'coal tit' with 'martin', and transposed 'martin' to 'marten'.