Sumner didn’t like John, he went out of his way to remind him of it too, and it hit John right to the core every time.
John needed approval, he always had, he also fought really hard to make sure nobody ever found out again.
Nancy had figured him out, worked out how to get the unattainable John Sheppard to her self, even made him sleep with her, but even she couldn’t make his body respond to a female.
She had eventually left him when she realised even marriage would never make it work.
The whole debacle had only reinforced that nobody could ever again realise just how easy it was to 'make' him obey.
He had enjoyed Antarctica, it was beautiful and peaceful, so giving it up to join the Atlantis expedition was difficult, Elizabeth he could ignore,
but O'Neill had that Alpha vibe that he couldn’t dismiss, so he went, knowing Sumner would be hell but at least he would never be given any kind of responsibility by the man,
in trying to 'keep him in his place' Sumner would be protecting him, which worked for John's sense of humour too. Then the bastard had to up and die.
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