Robin

Robin was an evil witch who lived in San Francisco during the 1960s. In 1967, she and her warlock boyfriend, Nigel, found out that the Halliwell Manor was built over a spiritual nexus. She befriended Penny Halliwell, and the two became best friends. The two helped plan a "magical be-in," and invited several of their witch friends to come so they could tap into the Nexus' power. However, Robin and Nigel planned to massacre all of the witches there and take the Nexus' power for themselves. Penny suspected that evil forces might try to disrupt the "be-in," and had everyone take and bless crystals to ward it off. Robin then found an excuse to sneak to the attic so she could unleash evil in the manor before the crystals could be deployed. Penny's husband, Allen, walked in on Robin in the midst of her chanting; he'd noticed she was acting strangely. Robin killed Allen with a fireball. Penny flew into a rage at the sight of her husband's body, and killed Robin on the spot. Penny had been a pacifist for some time, but Allen's death at Robin's hand turned her into the dedicated demon and warlock hunter she remained for the rest of her life.

Almost 37 years later, Paige was sent back to 1967 after putting on a pair of go-go boots Grams had enchanted. Later, she walked in on Robin as she was about to kill Allen, and temporarily distracted her. Allen tried to talk Robin into renouncing evil, but only succeeded in making Robin angrier. Paige knocked over some marbles as Robin was about to throw another fireball. Robin was knocked off her feet and killed by her own fireball, temporarily disrupting the timeline.

Robin's fireballs looked similar to those generated by powerful upper-level demons, such as the Triad and the Source. She was also as kill-crazy as any evil witch; she was visibly disgusted at having to pretend to be a hippie, and her voice and demeanor became noticeably more sinister when she dropped her hippie persona.

Appearances
Robin appeared in a total of 1 episode throughout the course of the series.
 * Season 6 -
 * Witchstock