Damn it, Pinkie
All things considered, it was a rather normal morning at Sugarcube Corner. Pinkie somehow got confetti clogged in the sink, the twins were being a bit rowdy, the Cakes had their usual resigned demeanor as they took care of the twins, and here stood Steve at the register, bored out of his mind. It being a Sunday morning, there wasn't any work for ponies today, and it was still too early for anyone to walk in, considering most were sleeping in at this time. Steve had questioned the Cakes as to why they opened up despite this anyway, and the Cakes had reasoned that it was always good to be prepared for a customer.
As per usual for Sunday mornings as well, Steve was assigned to cashier and Pinkie to baking. The Cakes, knowing how empty Sugarcube Corner is during this time, were upstairs, tending to the twins. The twins had played and worn themselves out, so it was time for their nap. That left Steve and Pinkie alone on the main floor.
So Steve stared at the front door, his mind wandering. Not to anything really specific, mind you; it was almost like he was dreaming, seeing & hearing things but never getting a concrete image of them, becoming a mindless whirl of colors and sounds that had no meaning. As he did this, though, he came to realize that he was licking around inside of his own mouth. So, he decided to instead try to focus on feeling the contours of his mouth hole. It felt a bit boring, until he slid his tongue over the top part of his mouth.
Weird, Thought Steve, It feels... Really odd. From the teeth to halfway back, it felt bumpy and ribbed. Then that feeling would stop and give way to being really smooth, just before the uvula.
Steve must have been focusing on his mouth a little too much, cause he hadn't noticed that Pinkie was standing on the counter in front of him, looking at him quizzically.
"Hey Steve!," Pinkie exclaimed, bouncing up with excitement, "Why's your face all twisty like that, huh, huh? You feeling okay?"
Steve jumped a little out of surprise, before he looked at Pinkie, trying to gather his thoughts. That's when Steve got an idea... Pinkie was always up for a good laugh, but Steve had never tried anything beyond what was considered to be clean humor. He had figured that venturing into other territory was weird, considering they were different species. Not to mention, Pinkie seemed far too innocent to understand such humor. Might as well test the waters, Thought Steve.
"The top of my mouth feels really weird," Steve said, Pinkie raising a brow, "... Do you wanna feel it?"
Pinkie blinked, "Wha-..."
"With your tongue?," Steve threw in, giving her the cheesiest and sleaziest expression he could muster.
Pinkie stared at him with a blank expression. Now Steve was worried. He'd taken a big gamble, and how things were looking, he had missed the triple 7 and instead gotten triple of a pile of cow dung. In his time here, he also knew what an angry Pinkie was like from the time he broke a Pinkie promise. He hadn't taken it seriously, snorting at the dumb Pinkie and pinky pun, until she breathed fire and ate his pillow when he failed to pull through with said promise. He was sweating profusely as he looked around, trying to find the best possible escape routes, before he noticed that Pinkie's eyes were twinkling and she had a huge grin on her face.
"Oh absolutely! Wheee!," Pinkie yelled as she pounced on him, tackling him onto the freshly cleaned tile flooring. Mrs. Cake wasn't going to be too pleased about that.
"Wha- What the hell, Pinkie?!," Steve exclaimed as he struggled underneath her, trying to get away from her. This wasn't good. He had meant it as a joke, but Pinkie was taking it seriously. This had happened before when Steve would think up horrible prank ideas and tried to get Pinkie to laugh by telling them to her; He hadn't expected her to actually do them. Rarity still hadn't forgiven either of them for putting pudding in a diaper and rubbing it all over her... Or Rainbow Dash, when Pinkie had shaved her eyebrows and dyed her hair white.
"Open wide!," Pinkie exclaimed as she grabbed Steve's nose and pulled it back, forcing his mouth open. She leaned down and starting licking the top of his mouth with an analytical look on her face. Steve, at this point, had given up fighting. While unicorns had magic and pegasi had flight, earth ponies had extreme physical strength. In other words, escaping Pinkie's nonsense wasn't going to happen. He was, however, shuddering in disgust and trying to keep his tongue away from hers. He was screaming in his mind, feeling just... So, so violated right now.
"Wow, you're right," Pinkie said, finally pulling back, "It feels like licking a wet hissing cockroach. It tastes really good, though! Kind of like raw uncooked salmon but with a different texture! Ooh, ooh, maybe we can put your mouth on the menu!"
Steve didn't respond. He was crying and shuddering, staring at the ceiling and wallowing in despair. His mind was either in overdrive or it was long gone; either way, he wasn't going to be recovering anytime soon.
Pinkie looked down at him for a few seconds, confused as to why he wasn't excited about the new menu option, before she herself had an idea.
"Ooh, I know! Twilight will definitely want to do research on what a human mouth looks and tastes like! I'll go get her right away!," She said as she zoomed out of Sugarcube Corner. Mr. Cake walked up to Steve and patted him on the shoulder, wearing a small smile of sympathy.
"Don't worry, Steve. We've all been there. How do you think I met Mrs. Cake? She used to be a dentist, you know."
Steve grimaced at the mental image in his head.
So here Steve miserably sat in Golden Oaks Library, long dead on the inside. Twilight had papers and pens flying about everywhere, taking notes and sketches for Celestia as she furiously and thoroughly studied his mouth.
... With her tongue.