OK, so I got really carried away. Somehow this prompt turned into a whole headcanon about Sparrow & co (Frost, Octavian, Loretta, German, Izzy, Simon, and Nadia) in the zombie apocalypse and getting picked off one by one until only Sparrow/Frost are left, trapped by the horde, and forced to commit suicide (or murder/suicide) to avoid the much worse fate of joining it.
Parabellum Zombie Apocalypse AU
http://otpprompts.tumblr.com/post/138723891031/imagine-its-the-za-and-your-otp-is-the-last-of
OK, so I got really carried away. Somehow this prompt turned into a whole headcanon about Sparrow & co (Frost, Octavian, Loretta, German, Izzy, Simon, and Nadia) in the zombie apocalypse and getting picked off one by one until only Sparrow/Frost are left, trapped by the horde, and forced to commit suicide (or murder/suicide) to avoid the much worse fate of joining it.