Yureina was a name of my own creation for my Holy Priestess in WoW [http://i1085.photobucket.com/albums/j427/YureinaL/WoW/YureinaFinale4.jpg]. I took up the name in early 2008, and the character saw a rapid rise to becoming the best of my WoW characters even after years of crazy PvP and PvE achievements (including opening AQ on my warrior). As my priestess became so successful, I decided to use the character to represent my online identity as a whole. Although I ended up quitting WoW in April 2010, and then for good in November later that year, I kept the name because I strongly identified with the character I created, as well as the many achievements I had with her. The name, therefore, became a permanent identity for me, even though by now it isn't really linked to my WoW character anymore.
Now, the name is very much its own identity. :3
P.S. My nickname was "Rei" from day 1. Only much later did I find out that Rei was the name of a character in Evangelion. Since then, Rei Ayanami and this username have been inseparably linked together, with the Rei avatar being another part of my online identity. :3