The main character is, of course, Buffy Summers, played by Sarah Michelle Gellar. Her best friend, from the very first episode, is Willow Rosenberg, who has developed her powers of witchcraft and will probably play an important role in the plot of season 6.
Buffy's been quite in love with Angel, much to the chagrin of Alexander (Xander) Harris.
Buffy is quite different from the other slayers, including the one in the comics