The journals of Rupert Giles. Vol. 1 - Nancy Holder

Buffy Summers is hip, modern, and utterly immersed in pop culture. Rupert Giles is a traditional Englishman whose idea of bliss is a good book and a strong cup of tea. Difficult though it may be to come up with an odder couple, the duo have managed to avert their fair share of apocalypses.
One thing they can't seem to conquer, however, is Buffy's bad birthday luck. At eighteen, she is subjected to a Watcher's Council Cruciamentum, a test of her ability to handle danger without the help of her Slayer powers. The rite, however, also tests Giles' attitude towards both his charge and his calling, and leaves their relationship on a rather different footing.
One year on, when Buffy's friends throw her a surprise party for her nineteenth, Giles finds himself feeling useless and out of the loop, and an evening spent in the company of his one-time crony Ethan Rayne means that his problems are only just beginning. But it is at the Slayer's twentieth birthday gathering that both Buffy and Giles are forced to re-examine the nature of blood ties and the definition of family - or risk losing a mutual loved one more important to them - and the fate of the world - than either ever imagined....
Based on the episodes HELPLESS, A NEW MAN and BLOOD TIES.