Mass Effect Big Bang time..
The story is available here at Archive of Our Own: [link]
Disclaimer: All characters owned by Bioware or the BBC.
Word Count: 21K ish
Characters/Pairings: male default Shepard/Kaidan Alenko
Warnings: NC17 in places, violence, sexual situations between default male Shepard and Kaidan Alenko
Spoilers: Ending of ME3 with some dialogue lifted from the extended cut, none for DW
Summary: Shepard faces a challenge he never expected when a strange, strange man in a big, blue box comes calling.