Rainbow Dash had never actually tried the cider in Canterlot, but judging by Twilight's tolerance- or lack thereof- for Apple family cider, she was one-hundred and twenty percent sure that the rich, powerful and famous drank cider that was weaker than a papier-mache bust of an ant. Two mugs and Twilight was about to fall flat on the floor. Two mugs and the unicorn's expansive vocabulary and perfect diction had dissolved into mumbling and sentence fragments. Two mugs and she was swinging her forelegs around arrhythmically whilst slurring a song that wasn't even being played on the one record player in Sugarcube Corner. The pegasus watched in slight horror as Twilight bumped into one of the ninety-nine red balloons that filled the spacious party room that encompassed almost the entire upper-floor of the bakery. Now, Rainbow Dash didn't know much about physics, but she was sure that a small, helium-filled balloon should not be able to knock over a pony. Leave it to Twilight Sparkle, one of Equestria's proudest scientists, to break the very laws she enforced on a regular basis. The purple mare was flat on her back, lain out upon the cider and icing covered floor like a rug, laughing, still loudly singing a pitchy rendition of a song no one else seemed to recognize
"I'm me...Me be..."
Rainbow, whom was on her fifth mug and was still (mostly) sober, sighed at the rolling unicorn. She looked up at her friends and saw exactly what she had expected to see: A couple of her friends were respectfully trying to suppress their chuckles (A losing battle in a situation like this), but most of the room had taken to watching the scene unfold as if it were a performance by the town's newest comedy troupe. However, to Rainbow, this was far from a Pony Python sketch; this was an embarrassment. If it weren't for the fact that Twilight would occasionally wretch and moan amidst her out-of-key renditions, the pegasus would have guessed that this was some kind of prank, or even pay-back of some sorts. She didn't know the answer, but there was one thing that she did know: She had to get Twilight out of this perturbed predicament, lest she become the punchline of the town's jokes.
With little hesitation, the Element of Loyalty scooped up the Element of Magic, and carried her out of the room, down the stairs and out of Sugarcube Corner; much to the dismay of several ponies, including Pinkie Pie, whom had, somehow, produced a large tub of popcorn to enjoy the spectacle with. The party pony sighed, devoured the rest of the popcorn in one gulp, and the party burnt on into the night
"Oh no...It go..." Twilight cried at the slowly-fading, plastic pastry-encrusted bakery. As the two ponies rounded a corner, and the saccharine temple disappeared from sight, Twilight bleated out one last time, "...It gone...bye-bye." If it weren't for the fact that she needed both of her forehooves firmly planted on the ground to keep moving, Rainbow would have slammed one against her own face a long time ago. Everypony had given her advice on how to deal with a relationship; what to say, when to say it, what kind of flowers to give your partner on her birthday, what kind of candy to buy her for Hearts and Hooves Day, etc. What they hadn't told her was how to deal with a drunken unicorn. Rainbow wanted to put a muzzle around Twilight's mouth and cease all her babbling, but at the same time, Twilight was also one of the most powerful unicorns in a Equestria when it came to magic. Rainbow was scared to death that, in a drunken haze, the purple mare would hallucinate a spider on the back of her neck, attempt to incinerate it, and wake up, sober, to the sight of Kentucky Fried Rainbow Dash. It was this fear that kept making the pegasus duck each time Twilight moved, and it was this paranoia that kept her hooves moving, praying that the library was just around the corner. As she bounded around yet another familiar corner, Ranbow was treated to the silhouette of a tree, and she quietly rejoiced, thanking Celestia, Luna and whatever other deities may exist in the universe, for letting her get Twilight home without having to suffer third-degree burns in the process. She ran to the door with enough velocity to pull off a Sonic Rainboom, nearly knocking over a groggy Spike as she charged through the door and up the stairs
Twilight tried to knock the glass of water away, swinging her hooves wildly through the air to no avail. She tried to push it away with telekinesis, but simply wound up grasping a nearby copy of The Unabridged History of Equestria, nearly crushing poor Spike when it fell to the floor with a clatter. Finally, the purple unicorn succumbed to Rainbow's pestering, and meekly sipped the water - nearly spilling the entire glass on her bed. Satisfied, the pegasus set the glass down on the night table, leaned back on her haunches, and exhaled the breath she had been holding for the past hour. She had another bill to add to "The Law of Rainbow Dash": Never, under any circumstances, let Twilight Sparkle consume more than one mug of cider. The new rule was pending ratification, but Rainbow was sure it would make its way through the houses of coolness, awesomeness and radicalness.
Rainbow chuckled at her ever-increasing level of "eggheadedness", and nearly passed out: Carrying Twilight around took more out of her than she had originally anticipated. Rubbing her tired eyes, Rainbow arose from her slouched position, and began to make her way over to the guest bed (which was conveniently placed two paces away). However, her progress was halted by a desperate, purple hoof and pleading, violet eyes.
"No...No leave..youfsleelzwitehm..." the unicorn blacked out mid-plea; her point made it across, though, and Rainbow smiled, happy to oblige. Carefully, she inched her way under the covers, briefly moved around to get into a comfortable position and wrapped Twilight in a tight embrace. The unicorn briefly regained consciousness and gave the pegasus a light peck on the muzzle before passing out again. Rainbow smiled and tossed the "never let Twilight drink" bill into the garbage.