I don't own Criminal Minds. This idea wouldn't leave my head. I couldn't find Emily's middle name, so I made that part up. Enjoy.
The Satchel
The BAU team was settled in for a long flight to California. Made even longer by the fact that they'd just finished up a case in Maine. They'd already discussed the new case, and had separated to relax for the rest of the flight. Rossi was reading. JJ, Derek, Emily, and Hotch were playing cards, while Spencer napped. The Plane hit a bump of turbulence, and Reid's bag spilled out from its place on the floor. "Oh no." Emily said as she got up to collect the scattered items for the still slumbering man.
She didn't pay much attention to what she was picking up until her fingers wrapped around a little black velvet box. Her free hand went to cover her mouth as they hit another patch of turbulence. "What the-." The young Dr. Reid began as he sat up and began looking around him. When his eyes fell on Emily and what she held in her hand, his widened. "Where did you get that?"
"The turbulence knocked your bag over and this fell out." Neither realized the team were all watching them. "What is this Spence?"
"It's an anniversary present." He replied.
She looked down at the box. "May I?"
"Uh.. sure."
JJ came over as Emily opened the box and looked inside. "Aww Spence its gorgeous. Who's it for?"
Her question was ignored however as Spencer kept his eyes on Emily, whose eyes were completely transfixed by the engagement ring that was sitting in her hand. "Is this-?"
"That's an engagement ring." Derek said when he came over to see what the fuss was about.
Spencer slid off of the bench onto the floor so he was crouched in front of Emily, and he took hold of her empty hand. "Emily, I made reservations at your favorite restaurant, spoke to your father, and planned everything down to the last detail to make my proposal as romantic as possible. Since nothing in our lives ever works out the way we plan it, I should have expected something to come up." JJ gasped when he said proposal and was looking between them, trying to Figure out when they'd gotten together. "Since the cat is out of the bag, now seems as good a time as ever.." he hesitated as the nerves finally hit him. "Emily Eleanora Prentiss, will you marry me?"
Spencer realized someone had called Garcia when he heard her squeal in the back ground, but he was too focused on Emily to care. He was starting to get worried, when she snapped out of her shock and yelled, "yes!"
Spencer pulled her into a jubilant kiss, before pulling away to put the ring on her finger. "I love you so much Em."
"And I love you Spence."