Of course, I am only playing with the characters and settings created by JK Rowling, and will in no way profit from this silliness.
The Quill is Mightier Than the Pessimistic Disposition of Severus Snape
Hermione dumped the contents of her bookbag on her bed and rummaged furiously through the assorted rolls of parchment, grubby quills, bottles of ink, a dirty hankie—she dropped this in her laundry—books of various sizes, and ugh!, a half eaten apple from three days ago.
Not there, not there! Where was it? She laid out all her quills again. How could she have lost it? Hermione stopped sorting through her belongings and took up pacing across her room.
This was important. This was vital. It had taken her hours to find just the right thing, and now it was gone! Gone! She'd spent six and a half hours in the old musty shop at the seedier end of Diagon Alley, and after that she'd had a severe allergy attack that kept her up most of the night. Now it was all for nothing.
She kicked her rather solid chair in frustration and bruised her toe.
Hopping to her bed and sitting down to cradle her throbbing toe, she tried to think of where it might be. She knew she'd put in her bookbag, carefully, even, because her bookbag was always messy. Then she'd come straight back to her rooms in the castle to prepare lesson plans for the following day. Her bookbag sat on the floor by her desk all night. It sat there during breakfast in the Great Hall. She had retrieved it before her first class (a studious group of Ravenclaw third-years, who didn't give her much trouble, thank goodness, as she was never fully awake until halfway through it). But she hadn't gotten into it until her second class, those rambunctious Slytherin and Gryffindor fourth-years who got along depressingly well, and made the class a nightmare for her if she had had a late night and wasn't on her toes.
Her second class! She had carelessly told innocent-looking Rob Haddlewel (she knew perfectly well the extent of his innocence) to grab one of the spare quills from her bag when he had shown her the fluffy scraps that were the remains of his own (and then she had given an unabashed Martin Maald detention).
If she were lucky, the quill was still in the classroom. If not…. She preferred not to think about the trouble Rob would get up to if he figured out what that quill did.
Racing through the corridors, startling two older Hufflepuffs in some quiet conversation with a younger Ravenclaw, she slammed through her classroom door and dove at the clean, white quill she saw sitting on a desk near the back. Gasping with relief (and because she had run quite fast), she looked it over. She was sure it was the same quill, but perhaps she could find someone to help her prove…
She walked briskly towards the staff room and caught Filius leaving just as she approached.
"Filius!" she called, "could you give me a hand, here? I need to verify the, um, function of this quill."
Filius was charmed to help the lovely young woman, and said so.
"Wonderful! Here, I just need you to write something for me. This quill will only write the truth," Hermione paused as she considered whether to make Rob Haddlewel retake his quiz, and decided against it, "so I need you to try to write something ridiculous, to make sure it won't let you. How about 'I bathe in peanut butter to keep my skin youthful?"
Filius looked at her strangely, and promptly wrote 'I bathe in peanut butter to keep my skin youthful.'
"Hmm," said Hermione, "Well, perhaps this isn't the correct quill. I was so sure. Oh dear."
"Not at all," replied Filius uncomfortably, "but I don't know how you knew, for I've never said a word, not one, to anybody."
"Oh!" said a shocked Hermione. Then she began to giggle.
Affronted, Filius left her standing in the hallway.
Still smiling, she made her way to the dungeons, and boldly marched up to Snape's door. She knocked loudly. When there was no answer, she yelled, "Open up, Snape! I know you're in there sulking. I can prove what I said now, so let me in!"
Just as she was about to draw her wand and remove the door, and walls, if necessary, the door opened slightly. Jamming her foot into the crack, she waved the quill at the nose visible through the aperture.
"Do you know what this is?" she cried triumphantly.
"No, and I have little wish to," came the sulky reply.
"Of course you do." Hermione switched to persuasive. "This is a quill from a bird that has been fed Veritaserum from hatching. It can't lie. Do you know how many knock-offs I had to go through before I found one that was the real thing? Over six hours, Severus! I'm going to write down what I said, and you're going to believe me."
She thrust her hip against the door, and it gave enough for her to wiggle through, leaving her mussed and flushed inside Snape's office.
Snape stood looking at her with an expression of mingled distaste, amusement, and something else that she hoped was dawning belief.
She walked over to his desk and grabbed a piece of parchment. As she dipped the quill in the ink bottle, she began to tremble just a little. What if she was wrong? What if she hadn't understood? What if Severus really didn't… She didn't finish the thought; instead, she unsteadily scrawled 'I, Hermione Jane Granger, love you, Severus Snape' and then, before she had time to think any more unruly thoughts, lifted the paper and flourished it under Snape's distinctive nose.
A mocking smile marred his face. "And why should I believe this quill will force the wielder to write truth? Simply because you tell me so?" He was desperately afraid that this would all turn out to be a terrible joke.
"Do you not love me, Severus?" Hermione asked gently.
"Of course not! How you could support such a preposterous notion is beyond me," he returned snappishly, and immediately began to head for the door.
"Fine, then," challenged Hermione clearly, "write that down for me, will you?" She thrust the parchment at him.
Reluctantly, he took the quill and parchment and turned to face Hermione. If he wasn't to be hurt, then all he had to do was lie and tell her he didn't love her. It would be better for both of them. Still, he was loath to put the lie in writing.
Slowly, he wrote 'I do not love you, Miss Granger.'
Hermione let out a little squeal, and Snape was astonished when he looked up and saw her face transfigured with joy. Confused, he looked back at the parchment. Clearly written in his own hand was the sentence 'I love you, Miss Granger.'
He looked back at Hermione, a little wonder lighting his eyes. She did love him. There was no joke.
With a swift movement he gathered her into his arms and kissed her. When they parted (some time later, and with both of their robes somewhat rumpled) he smiled down at her and found her laughing up at him delightedly.
"Come," he said, "It is time for dinner. I dare not leave my Slytherins to the tender mercies of the other teachers."
Hermione acquiesced with only a slightly disappointed expression. It was dinnertime, after all, and she was hungry.
"Severus," she ventured as they walked, "have you ever wondered how Filius has kept his skin so young-looking?"