Saber (セイバー, Seibā?) is a Saber-class Servant summoned by Koharu in "After" the Holy Grail War in Fate/Requiem. Koharu and Saber were noted as being undefeated prior to the beginning of Fate/Requiem.
Saber is a womanizer like his father, but also has a snarky attitude and teases his Master.
One of his two swords is known as the Sword of David.