Savil

 is one of the members of the Followers of the Apocalypse in 2161 and a guard in the Followers' Boneyard Library.

Other interactions

 * could shed some light on the activities of the Followers to the player, as well as give them some weapons training.

Appearances
was cut from Fallout, apparently planned to be an armed Follower patrolling the library. However, in the released game there are no armed Followers, just students.