Dimir...
House Dimir... twelth guild of ravnica, the secret guild, the guild of thief and assasssins (if you don't know what im talkin about, get yourself these books; Ravnica, city of guilds, Guildpact, Dissenssion from wizards of the coast, the guys who made D&D)
for me, Dimir signifies secrets, tretchery, machinations, plots, coup d'état, etc.
so thats what i had to say, ry if it makes no sense but hey, i took out what i had to say