A/N: Sometimes, when I have the availability to fulfill prompts, I open up a window of time for people to submit an idea to my writing tumblr. This is the product of one of those times, though I keep on forgetting to crosspost.
The prompt for this one was "It's Clara's 50th birthday and she only has to gently remind the Doctor of it. Fill in the intermittent years and details however you choose."
The Most Important Day
The chime sounded out over the intercom and the students began to settle down into their seats for class. Once their books were out and they were quiet, their teacher began the lecture.
"Now, can anyone tell me what is significant about today?"
"Does it have to do with the lead-up to World War II? That's almost been a hundred years, and lots of people are making a fuss," a student asked. The teacher shook her head.
"Nope, try again."
"It's the fifty-sixth series of my favorite show on the telly," another student mentioned.
"That's nice, but not quite."
"It's Tuesday."
"While factually correct, not precisely what I'm looking for."
"Then what is it?"
"Today is a day that is very special without anyone ever really knowing it," the teacher said. She leaned against her desk, the light from outside catching in her greying hair. "Today, a chapter in a book began, a new life was born, a new beginning started. Today is the best day in the world and, if I'm allowed to say it, the best in the entire universe."
"Why's that?" a student asked. They had sat through lectures like this before, when their teacher really was not feeling keen on teaching the course material, and sometimes picking apart her dialogue was more fun than when she had them analyze their favorite books for class instead of assigning something outright. "Is this another riddle?"
"Not necessarily a riddle, but a fact wrapped in an opinion, that had been digested with a proven theorem, and chased with a large helping of reassurance," she replied. "Today is an important day from the way I see things. Maybe not the way you see the world, but to you, the first page of that book is just a rotting leaf."
"Of course, ma'am, and I'm going to the Moon," a student snarked. Their classmates giggled, though the teacher smirked along with them.
"You better hurry; I'll be up there in eleven years if you want to beat me," she quipped. The class laughed again and she held up a hand to silence them. "It's important because…"
"…it's the only day the caretaker can interrupt class and get away with it," a grey-haired man chuckled from the opened doorway. Dressed in the caretaker's smock, he held a broom in one hand and a dustpan in the other, both of which he leaned against the doorjamb before entering. He sat down on the desk and wrapped an arm around the teacher's waist, taking in the sight of her with love and admiration. "So, you think you can figure it out yet? What sort of day is important to a couple of old codgers like us?"
"It's your anniversary," a student guessed. The teacher rolled her eyes.
"That's next month—remember: eloping does nothing but upset your dad, yeah? Who else has a guess?"
"It's your birthday," someone in the front row said.
"Aye, very good," the caretaker smiled. "Did your Auntie Courtney tell you that?" The student nodded and the man nodded. "She is very wise to remember. Now, all of you, I want you to open your books to the bit about Oscar Wilde, and read it until the bell rings. Your dear teacher has an appointment with me in my office."
The teenagers all oohed as the caretaker lead their teacher out the door and into the corridor, ignoring her face as it turned a bright red. They walked towards where his office sat, with her growing increasingly impatient.
"I don't know why you felt the need to do that," she hissed. "I'm their teacher, older than some of their parents. I'm not supposed to have a sex life, especially not one with the caretaker of all people."
"Then we've been doing a poor job at that, haven't we?" he mentioned, flashing his teeth. As they entered his office, he hung up his "GO AWAY HUMANS and Chesterfield" sign and politely opened the door to the TARDIS, which was sitting in-wait. Stepping inside, the teacher walked straight up to the console and spun around, leaning on it as she had been on her desk minutes before.
"…and you really think you can get away with this?" she purred. The caretaker grinned manically as he approached her, putting one hand on her hip and the other on a lever that flung them into the time vortex. He bent down and pressed their lips together before whispering in her ear.
"Happy fiftieth birthday, Clara Oswald, and many more happy returns."
"Oooh, I take it my sticky note helped?" she teased.
"Number, yes, birthday, no," he murmured. She couldn't tell which of his words were lies and which were truth. It did not matter though, for she draped her arms around his shoulders and pulled him in for another kiss.
She let go of him when she needed air, allowing him to look down into her eyes. In the pulsating bioluminescent lights of the TARDIS, he could see her as she truly was: not someone's ageing Literature instructor, but a vibrant woman with wide brown eyes that matched her hair and a spark in her that was far from fading.
"Now of all of time and space, where would you like to go first, milady?"