Well, your avatar, minus the purple highlights on the cheeks, looks pretty ash-gray to me. There's no real world analog, because people that have "ashen" skin tones are usually very ill, if not dead.
I thought of a good example: here.
Except that if you look at the description of the Mwangi people, it says:
The appearance of the Mwangi people mainly depends on which subgroup they belong to. The four main ones are Zenj, Bonuwat, Mauxi and Bekyar. There are certain generalities that are true of all the varied Mwangi. Their skin is always dark, varying from dusky through grey to coal black skin tones
(Emphasis mine.)
Usually when a person is described as "ashen" they're not just dull, they're pallid and drained of color. The Mwangi are a dark-skinned race, and this is a fantasy world, so actually being gray isn't necessarily precluded.
