So, in Cube Escape: Theatre, we go into Bob's brain and pull out white cubes, extracting his memories in the process. One of the memories is of a tree where, after wiping away window fog or something, you find a heart shaped carving containing the letter V. This has one use in the game as representing the number 5, but I suspect it has another meaning as well. White cubes are good memories, and if he's having good memories of it, I'm guessing that what he's actually remembering is carving the letter V into the tree, like couples might do. So I'm guessing that the Young Woman's real name actually begins with a V.
Additionals, since white cubes are good memories, his white cube memories are the tree where he carved his girlfriend's initial, her hand, the moon and her crotch. Reeeeal subtle, Rusty Lake.