In Season 1 of Buffy, Willow was sophomore student in high school that nobody talked to because she was extremely smart and shy. She was constantly bullied by the popular girls in Sunnydale High School, who were Chordelia and her followers. As she befriends Buffy the viewers start to see a change in Willow. When she is bullied again she stands up for herself and replies to the insults, which is very out of character for the Willow in the first couple of episodes.As the season goes on Willow discovers that she is a witch and she starts learning about magic from Giles, she also becomes an important member of the Scooby gang of Buffy, since she becomes the logic and reasoning of the group. Her wardrobe in the season also starts to change and she goes from wearing preppy homemade looking dresses that she wore on the first episode to more fashionable clothes.
Willow gets into a relationship with Oz, a werewolf played by Seth Green. He first appears in the episode " Inca Mummy Girl". Oz and Willow have a happy relationship until Chordelia and Oz find Xander and Willow kissing. Then they start to have fallouts, but by graduation their relationship is back on track. When they get to college Oz meet another wolf and he cheats on Willow with the female wolf called Veruca. He sees that he is a wolf all the time and so he is afraid of hurting Willow so he leaves. His absence marks the period were Willow starts getting romantically attached to Tara and they become the first lesbian couple on television.
Willow and Tara have various problems in their relationship once Willow becomes addicted to magic, but eventually they resolve their differences and get back together. As everything is pure happiness between the two of them Tara is shot and she dies. When Tara is murdered Willow hurt and anger transforms her into the villain and she is a strong witch looking for revenge; eventually Xander's friendship saves her from total corruption.