Agent Brandubh
He is in Black Citadel near the refuge camp. http://dulfy.net/2013/03/26/gw2-dead-drops-secret-contact-living-story-achievement-guide/
Thank you very, very, very, very, very, very much.
There. 15 characters. Ya’ll can count them. :|
I’d consider lowering that to 11 with spaces and punctuation so we can say “Thank you.” :p