The peroxided bloodsucker played by James Marsters first showed up in Season 2’s “School Hard” episode and quickly established himself as a villainous nemesis whose fighting prowess — and ability to land a pithy quip — rivaled Buffy’s.

He eventually (and grudgingly) became an ally of sorts for the slayer and her friends; when he fell in love with Buffy in Season 5, things got really interesting.

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