Nyreen was created as a foil for Aria T'Loak, a past lover of the crime lord with a very paragon outlook on the world. One of the main reasons I adore the dynamic between Aria and Nyreen is that the turian can see good in everything. Even on Omega, one of the most crime filled stations in the galaxy, she can see the good in people that live there and the good Aria does in keeping them safe and giving them a place to call home if they want it.
It an unfortunate end that she meets, but helps develop another side of Aria that we don't get to see until that point.
Ahh, what a beautiful rendition of Nyreen. *-* She only lasted one DLC storyline but she somehow became a favourite of mine so quickly. I love this! <3