In an alternate, "good" scenario during the final battle, Rin is able to save Saber from fading away by extending their pact and turning her into her familiar. Having fallen unconscious during the battle, Shirou wakes up back at his home and initially believes Saber to have disappeared. However, he is surprised to see her alive and well in the apartment dojo. Rin enters and congratulates everyone for their victory in the Holy Grail War. While the three are out in the city, Rin explains how she managed to save Saber to Shirou, and adds that they will need to work together to sustain Saber with mana to ensure she stays. Shirou argues that Saber became a Servant in exchange for the Holy Grail and that she should be set free now that it is gone. However, Saber assures Shirou that she is staying out of her own volition because she wanted to stay with him and Rin, and because she wanted to find an answer to her own ideals after Archer criticized them. Rin then decides to further train Shirou in magic, while Saber trains him in her combat techniques. (thetvdb.com)