Draw a procedural cube in VR?

Hey everyone! Hoping someone will have some insight on this or be able to point me in the right direction.
I’m trying to draw a cube a in VR. This is what I’m going for (the yellow point would be the axis/handle):

I tried to figure out the logic, but sure it’s woefully wrong:

Is there a simple way to accomplish this?

Drawing a cube in VR is like the basis of my whole starter project so any help would be immensely appreciated.
I’m like a week deep into UE4 and a non-coder, so I’m probably batting out of my league (lol).
Just hoping to get this going as a starting point.

Thanks so much in advance!