Guys, I'm at the end of my rope looking for this. Google searches, filtered, unfiltered searches on FF.net, posting to tumblr and other communities, and I got nothing.
This is a major shot in the dark, as I know this place doesn't get updated or checked often, but I've been searching for a fic I literally found a few days ago and then suddenly lost. I saw it on FF.NET, it was extremely well written, with the linear page breaks instead of anything else being used like CSICSICSI or XXXXX or anything like that.
It was a kidnapping trope fic, where Nick broke up with Greg originally, then they end up becoming trapped in this area back to back on chairs, with a guy who's whumping the crap outta both of them, and there's a bomb under their chairs and a flood happening, and they're eventually found...
In the interim, Nick manages to get Greg and he facing each other on the chairs, and Greg's about to go down and Nick uses his belt to tie them together. Pretty sure this was set post Greg becoming a CSI.
So hopefully, someone sees this. Take care, guys!