It's obvious that, on occasion, Solar Princess Celestia is going to get a little... wound up in her line of work. Usually when that happens, she'll recline back in her seat and read a good book while drinking some tea. But sometimes, tea just doesn't cut it.
Sometimes, she needs a little bit of Joe.
Celestia hides her nightly visits with Joe from Luna, but as she should know, you can't keep a secret from a little sister.
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Cover Art used with permission from http://m2cool.deviantart.com/