School librarian Rupert Giles is an Oxford University graduate. Despite his dreams of being a fighter pilot or grocer, he ended up in the family business of training and mentoring Slayers. After Buffy's Watcher died, he took over the role when she moved to Sunnydale. To think that he used to summon demons in his youth.
Giles became a father figure to Buffy, and is the group's voice of authority. He also speaks five languages, has a dry sense of humour and plays guitar! Romance-wise, Giles is a shy man but he enjoyed a relationship with colleague Jenny Calendar - who was killed by Angel. Giles enjoyed a brief fling with Buffy's mother, when the pair were under the influence of some questionable chocolate..
Giles was removed from his role as Watcher when he refused to endanger Buffy's life in a training session. But he continued to help her until she no longer needed his protection, and moved to England where he helped Willow to control her magic making.