immersion?

[SuzakuCMX]

I could argue that immersion = booting up a game with the intention of playing for a bit before bed, and then realizing it's now 5:30 AM, you look like a scarecrow, and you've got an important meeting at 10 AM.

"state of being deeply engaged or involved; absorption. "

You very well could, and I feel immersed when the world feels like a reality.