I tried my hand at it, here's what I found:
vla002e.mlx is the naked riley model
vla007b.mlx is minerva, the model of the girl that covers her
I found this tool to replace textures
https://steamcommunity.com/sharedfiles/filedetails/?id=343016567They didn't affect the cutscenes at all though, so it's either pre-rendered or the models are duplicated somewhere else. There's a lot of models and I don't know a faster way to check them, but right now I'm thinking they must be pre-rendered. I tried using renderdoc to see if it's actually rendering meshes but I couldn't get it to hook, I'm a noob at that though.
One thing I did find (pic related) is that you can copy the naked riley model and replace the other riley models with it, so when you play the game she's out there naked. With some better textures it seems like it would be pretty good for a nude mod, just too bad I don't see a way to replace the models in the cutscenes.
