For people like me who love to know shooting locations for videos, I thinking I have worked out at least one location in Guam where Reina was shooting her early scenes in the "First" video.
Just copy and paste these numbers into Google Maps exactly as they are, comma included:
13.503509, 144.788379
This should take you to a location in Guam called Ypao Beach Park. You can see the red roofed picnic shelters, and if you drop into streetview you can see the whole location clearly, and even the shower where she takes a shower, which is at 13.504163, 144.788882 (although it might be the other one 50 metres to the west).
Enjoy, if you are into location stuff. I haven't finished the video yet so maybe there will be other identifiable locations. I think the whole thing is in Guam though?