When they decipher the location of your world and calibrate the portal to return you to it, it will be to the exact moment from which you left. No one will notice your absence.

[His brow creases with sympathy, but he doesn't know this person, doesn't understand precisely what they may mean bit 'close', and has no intention of revealing his heart to them, either...though just thinking of the fact that someone he was very close to recently left and will most likely have no memory of him as they are from different worlds, may aid in his distance.]

I see. So what you do, you do for him. Or don't do, rather.