Ever since Sweetie Belle had began her magic lessons with Twilight, she had been spending quite a lot of time at the library. Twilight had enjoyed the extra company — sure, Spike and Owlicious were fine enough, but Spike had never been much of a scholar, and the owl wasn't one for conversation. Sweetie, on the other hand, was both. Granted, she wasn't the cleverest of ponies, but she was eager and willing to learn, and that was enough.
A few days ago, Rarity had left for Manehattan — apparently, a big client had wanted to see her work in person. Not thrilled with leaving Sweetie in the house by herself, she had asked Twilight if Sweetie could stay with her. Twilight had agreed happily. Now, with the days entirely to themselves, the two could do so many things their limited time didn't allow before. They were able to visit Canterlot, The Crystal Empire, even arranged a short lesson with Celestia. It had been a good week.
Then one night, Twilight heard a gentle tap-tap on her floor. Struggling to both open her eyes and turn on her lamp, she woke up to see Sweetie standing there, looking up with begging eyes and stuffed animal in hand. She softly squeaked out a single word: "Please?". After this request made the treacherous journey to Twilight's sleep-deprived brain, she pulled down the covers, patted the mattress, and scooted over. Sweetie happily jumped in, falling back asleep almost instantly. Twilight sighed, turning over. This could be a long night, but despite that, she still smiled to herself.