I did the "Two Sides of a Coin" quest a couple of days ago and this evening, Myvryna Arano showed up inside the Fighters Guild in Cheydinhal and gave me a "Mysterious Letter." My Altmer Knight is far too honorable to ever consider joining something like the Thieves Guild. I'm wondering, because its been a while since I did the Thieves Guild, if I can go to the waterfront and tell Armand Christophe that I don't want to join the Thieves Guild? Its kind of annoying to have that letter perma-bound into my inventory, and I don't like having a quest in my journal if I don't plan on finishing it.
I play on 360 so I can't use any commands to get rid of either the letter or the Quest.
Thanks in advance for any replies.