A/N : My apologies for those childhood would be scarred forever after reading this. I saw the two character's names and well, here is it. (yea, I wrote it. but dont come shooting me down.)

"What's the occasion?" Derek grumbled, slipping on his green pants and the ridiculous looking green shoes. Or, what was shoes. On top of his head, instead of a surgery cap, it was a hat--green.

"You should really ask Richard. He wouldn't tell." Addison explained, adjusting her own headwear and made a spin to see her skirt flare out, then land back down again.

"I feel like a leaf." Derek complained, at that, Addison turned to him with a glare.
"I feel like a milk maid." she said. Then he looked up to check her out, then let out a small laugh.
"Mary Poppins." he recognised. "You should be happy, and that glare there wouldn't fit your role." he pointed out, and she turned to him with another glare.
"Watch it, buddy."

-----

Derek and Addison entered the conference room just at the same time with the rest of the staff. No need to enter extra early or be late to attract attention to their already ridiculous costume. Then there stood Richard, dressed as 'Beast' from Beauty and the Beast, waiting as the staff filed in complaining under their breathes. Then, his eyes fell on one of them, his smile turn into a frown.

"Preston, what the hell are you wearing!" he demanded. The surgeon looked up to him with a raised eyebrow.
"There is no way you are going to make me dress up in a cheery character." he warned, chuckling when he saw Derek's outfit. Richard let out a grunt and folded his arms in front of his chest, challenging the surgeon to go on. But Preston stood on his ground, refusing to budge.

"Alright, fine." Richard gave in. "Loose the hook and the eyepatch. You'll be Captain Happy today."
Preston smiled, taking off the hook and pulling down the eyepatch. "I'd rather be called Captain Burke, if you don't mind. Captain Happy is too...happy for my taste."

Richard rolled his eyes and turned to the rest of the staff.

"Alright, you all must be wondering why I have you dressed up in cartoon characters. The hospital had organised a 'Children's Day' annually, and for the today of every year, you will come in dressed in such customes for the sake of the children in this hospital. To create fun for them... ... ..."

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"Hello, Dr. Poppins." Derek teased as he emerged from the back. Addison turned around, grinning as her husband approached her.
"Hello, Dr. Green-Pan." she countered, and at that, Derek's smile fell.
"Shut up."
"You started it first." she pointed out.

The both of them stood in silence beside each other as they went through the file in front of them, double checking again before signing it at the bottom.

"So..." Derek started, but let the word trail off. Addison looked up to him sideways.
"I can start something." he suggested.

"Oh yea?"
"Yea." he said, almost confidently. He signed the chart, handing it to the nurse as Addison did so in the next second.

"I could start corrupting fairy tales." he said, only receiving a raised eyebrow from his wife. "Care to join?"

"Mary Poppins is too happy to be corrupted." she pointed out. "And she's not really a fairy tale, is she?"
"You are not happy." he laughed.
"That's because you're not making me happy." Addison played along.
"I can make you happy." he said, the smile on his face turned into a smirked, his blue eyes shone with mischief as he looked into hers challengingly.

Addison took a pretend moment to consider. "You know, I hear Peter Pan flies. But I'll take the chance and race you to the on-call room."

They raced towards the on-call room, both breathing heavily as they closed the door behind them, Derek's hands moving to the back to lock it.

"You know," he said, taking a step forward to his wife. "This Peter Pan doesn't fly but his friend sure does..."

He slided a hand around her waist and pulled her up with another only to kiss her on the lips with love and desire. She smiled between the kiss, running a hand through his hair as she pulled him closer to her.

"Make me Mary Poppins."