I dont think it is very complicated to do that, surely Bethesda could do it if they wanted to. (In Animal Crossing, the game was never paused and things would happen when you weren't around.)
I would not like my wife being eaten while my Xbox is turned off -.-
-calls buddy- "Yo sup?"
"Not much bro,you gonna play Skyrim?"
"Oh shet,hell yeah dude,I'll hit you back later iight?"
"Alright dude peace."
-turns on Xbox360 and starts up Skyrim and loads savefile-
"HONEY IM HOME!"
-blood everywhere and wife is dead on the floor-
"ALDUIN!!!!!!"
Alduin: -trollface-