Princess Twilight,
It recently occurred that I'd been so busy with things here in Canterlot with managing nobles, my sister, and keeping ourselves in check that I hadn't kept any good maintenance on your old tower since the Tirekt incident. Not the one you slept in at the Summit--that tower is super clean, especially after I had the maids make sure not an ounce of dragon fear musk was left. You probably didn't smell it because you're used to it, but trust me, it was there.
Anyway, I tried visiting the old tower this week, but I hit a snag. The spare key I had to your tower was gone.
It wasn't stolen, at least not in the sense of somepony else stealing it. A close associate of mine found the key and decided to try it out on EVERY door to see which one it opened. "If there's a key, there's a lock!" she declared with a sparkle in her eye and a gleeful smile reminiscent of a filly going on a scavenger hunt. I couldn't stay too mad at her for that--I didn't tell her what it went to yet.
However, she did lose the key somewhere in the Canterlot commons, so I can't enter your tower anymore. At least not without breaking a window, but that'll just invite trouble. Anyway, in case you're worried about security, you might want to have the lock changed on the door. Just let me know, and I'll get a locksmith out there to get it changed ASAP.
Oh, and if you want somepony else to have a set of spare keys, I'll need a number on the spare keys to make and distribute properly. I don't want my faux-pas to be the reason some of your books mysteriously vanish while you're away, along with anything else valuable you may keep in there.
I look forward to a prompt reply on this matter, especially considering you still have a few special books here and there I'm certain are worth keeping.
Sincerely and apologetically,
Princess Celestia
Ah, there you are! Did you find the key yet?
I figured as much. Well, don't worry. I'll have it covered later, but you really must control yoursel--
That's a box of apology donuts, isn't it? Ponyfeathers, you really do know me too well.
I know how obvious that is! Just pass me a donut already!