I know it's only in the movies, but they always say that, if the perpetrator takes off his mask, you aren't getting out alive.
BG had no mask ... which didn't bode well to begin with... but as I read the post above, it occurred to me that there is a very obvious and powerful way to be one person controlling two victims. Lie to them. Tell them that, if they cooperate, he won't kill them. Undress, dress. Don't scream. March. Pose. Not all SA involves contact, he may have been a voyeur-- scares me to think what he might have filmed/recorded. He was with them for a very long time.... terror is real. He could have forced them to do whatever he wanted with the (false, insidious) promise they could live, even more cruel if he put the fate of each girl on the shoulders of the other.
They had no way if knowing what he wanted from them and what he ultimately did to them.
But HE knew what he wanted. What he wanted from them. And, whatever it was, once he got it, he killed them.
So brutal. And just minutes earlier, within the hour, they were very much alive, chatting happily about the things young teenage girls chat about.
If only the planks could have given out, plunging him first -- before he ever reached them -- into river below.