Caretaker

The Caretaker is a character appearing in Fallout 4.

Background
An agent of the Railroad, he appears at whichever settlement becomes the Mercer Safehouse upon completion of the quest. He is very jumpy and appears to have PTSD from the Switchboard incident when the Institute laid siege to the Railroad's former headquarters.

Appearances
The Caretaker appears only in Fallout 4.

Bugs
Though he is assigned to Mercer Safehouse, he can wander to other settlements and remain there permanently.