I think I'd heard it said, on a game show or something, that it was Yuri & Yoona who were roommates. Now, I don't know if that was when they were in training, or if it was after they'd debuted (it kind of sounded more like it was once they'd gotten underway & things were going/or rolling...) // but they had some funny stories to tell of each other's sleeping habits, and what happened when alarm clocks went off, things like that- but then again, I think they'd mentioned - unless this was in a separate appearance somewhere else ~ that they would collect their cell phones at night & everything; so it was real strict! (i believe they might have mentioned they'd discoverd, or found ways around this (to naviate): but I just can't remember for sure! (;