I got this idea for a one-shot after I remembered this quote from ABC's Castle.
BTW, I do not own Castle or BBC's Sherlock :(
Castle: How do you know when you're in love?
Beckett: All the songs make sense.
Molly Hooper sat behind her desk at St. Barts looking over her report of Mrs. Riverton's passing when the door to her lab opened. In walked John Watson and Sherlock Holmes loudly discussing John's latest girlfriend.
"John, you only met Maggie three weeks ago. You cannot possibly be in love," Sherlock scoffed.
"First of all, it's Mary. Secondly, it's been two months. And finally, yes, it's very possible that I could be in love," John argued.
Molly groaned. Of all the days those two argue about being in love, they had to choose valentine's day.
The two men turned to Molly in unison. Then a spark lit up in John's eyes.
"Molly, how do you know when you're in love?" he asked.
Sherlock rolled his eyes while Molly blushed a little bit. "I'm not sure if Molly is the best person to ask about being in love John."
Molly glared at Sherlock, "I wouldn't talk brainy boy."
Sherlock glared at Molly as John released a chuckle.
"So you're in love Molly?"
"I have been."
"So how do you know?"
Molly looked at John and answered him, "All the songs make sense."
She then looked at Sherlock with a slight smile, "Or you learn that you do count."
John looked confused at that last statement. Sherlock just smirked. And Molly just blushed.
So, not the best one-shot, but it is my first one-shot & Sherlock fanfic. Please leave a review! :)