Would be epic if Varric's nickname for Dorian turns out to be DHMG 
But it might be too long...
Varric: ... "Tevinter"?
Dorian: *shakes head* Come now, Varric, you can do better than that!
Varric: "Moustache"?
Dorian: Absolutely not! I don't care how fine my facial hair is, you aren't naming me for it. You don't hear me calling you "Chest Hair" on a regular, do you?
Varric: *wearily* Fine, then what about "Surprise Meatballs"?
Dorian: *raises eyebrow* Tell me you're joking.
Varric: *frustrated* Okay, how about "Dramatic Hands Moustache Guy"? We can shorten it to DHMG.
Dorian: Dramatic Hands M... oh, you're not even trying, are you?! And what is that supposed to mean, exactly?! *gestures dramatically*
Varric: ... Or maybe I'll just nickname you "Diva" in all my stories of the Inquisition, and call it a day.
Dorian: *splutters* What?! Inquisitor! Control your dwarf and his flights of literary fancy this instant!
Inquisitor: *smothered laughter* You brought it upon yourself, Dorian. You've been badgering him about this for days.
Varric: *shrugs and smirks* That's what happens when you incur the wrath of my muse, Pavus.
Dorian: Ugh! *throws hands up in the air dramatically and leaves the room in disgust*
Inquisitor: ... "DHMG", huh? Fitting.
Varric: *smug* I thought so too.