How come nobody, apparently, has noticed so far that "Kos" is coincidentally a short form for Koschei, creator of the universe in the Poictesme fantasy series by James Branch Cabell?
And Koschei has some other mythic variants too in multifarious creative works, see, e.g.,
http://urchin.earth.li/cgi-bin/twic/wiki/view.pl?page=KoscheiTheDeathless .
"Kos" is a pretty unusual name, frankly, and the tie to "Koschei" is just too much to pass up. I hope this doesn't boost Kos's ego too much, by the way.