There is a good reason Rarity - well, Cherry Spices - never lets anypony in her room until she is awake. It wouldn't do for somepony to stumble upon her if she's... not 'herself' as one might say. Before the last pieces of the costume are in place and proper enchantments in place. Before she is mentally ready to be Rarity again. Although that last part has gotten way easier over the years.
She even sleeps more and more in her costume, finding it confortable enough after years in it. Regardless, just to be safe... no pony enters in the morning and Carousel Boutique only opens its' doors way later in the day.
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So yeah, couldn't leave this idea alone just yet.
Some people I am too nice to mention here even have prodded me towards starting a tumblr, maybe based on this idea.
We'll see if anything happens. (Don't hold your breath though.)
Rarity, Those Confounded Ponies (c) Hasbro.
`anmari has been spreading her infectious positivity throughout our community for over 6 years. Throughout this time Ana has been at the core of all things devious, passionately developing an eclectic gallery, helping organise devmeets, participating in chat events and also recently completed dedicating her time as a Community Volunteer. We are absolutely delighted to bestow the Deviousness Award for May 2013 to `anmari, congratulations! Read More
Sta.sh
And how many pieces does that suit come in?
Bodysuit, each of the legs, tail and headpiece. At least, that's how I think of it.
I kinda figured as much; though it'd be fun to see Spike holding one of them out to Twilight and asking if she could pretend to be Rarity "just for a little while".
One would think they're not THAT commonplace though, as that would kinda drop the bottom off Cherry Spices' cover.