SGA fic: It's Complicated

I signed up for the Totally Unofficial Someecard Challenge, in which hackthis assigned someecards.com e-cards as prompts. Here's mine. And here is my story.

Title: It's Complicated [Off-site mirror here]
Fandom, Pairing: Stargate: Atlantis, McKay/Sheppard
Rating: PG
Word count: ~2,500
Spoilers: Set around season 2, with passing references to minor bits of information we find out in 3x15 "The Game" and 4x13 "Quarantine."

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