Watcher is an NPC that can be found in the Refuge. They have varied dialogue depending on the time of the Player's computer clock. They seem to believe that the timer in the countdown room is counting down to the end of the world.
Watcher has a distant personality, but does appear to care about Niko, as they will say Niko should not be up so late if the time is between midnight and 5:59AM in real life time. This may be attributed for children in general, however.