Xen: I think 3 is correct about the nude mod being a version of Fantasy Figures. Probably an older version, due to the lack of pubes.
The pose is contained in JOJO's version of CTAddPose, which itself is contained inside this mod pack: http://www.tesnexus.com/downloads/file.php?id=13193
Anonymous11: Anonymous9 -- there's a good chance that you can transfer the Oblivion models as a whole over to Garry's Mod, but it seems to be an unsupportable idea.
Anonymous12: Tessmage is working on transfering Model files from Source into Oblivion and most likely vice versa. I'm sure once they have the kinks worked out they'll have a guide or pre-built packs on how to do it.
The pose is contained in JOJO's version of CTAddPose, which itself is contained inside this mod pack: http://www.tesnexus.com/downloads/file.php?id=13193
GUM GUM