Shanny's Corner

Arthur and Eames are deep, possibly unhealthily, in love when they get stuck in limbo for what amounts to decades. While they're down there, they become so close, through near-constant sex and brain-sharing, that they literally become one person. Because they long to be so close to one another that they become inextricable from each other, their souls and their bodies become joined and fuse into one being.
They exist that way for ages in limbo.
Then they wake up. And have to deal with the shock of being apart. Think overwhelmed desperation, clinging, needing to be as close as possible because they no longer are physically connected and it's killing them.
Make it as angsty, porny, and/or disturbing as you please, but please let them stay together and (somehow) maintain their sanity in the end!