Seth Green as Oz

Oz is the newest recurring character on the show, and as far as I'm concerned, one of the most interesting. He is the most laid back, nonchalent, quirky guy at Sunnydale. He is completely candid, he makes interesting observations about the world (hey, did you notice that monkeys are the only animal crackers with pants?) and he was the first (human) guy cool enough to notice how fantastic Willow is.

Eccentric, guitar-playing senior Oz spent a long time noticing Willow Rosenburg ("Who is that girl?") and admiring her from afar before finally meeting her during the school's career fair. Not only did he get to meet the girl of his dreams, but he got to take a bullet for her! They definitely got off on the right foot, and they're relationship, of course, continued to develop from there. Willow assumed he was expressing computer nerd solidarity with his attention, but eventually it became apparent that he liked her, a lot. Their relationship hasn't been without it's complications, what with Willow having to let go of her jealousy over Xander's relationship with Cordelia, and Oz being a Werewolf, but they are currently a happy couple

Episodes with Oz
(All transcripts generously provided by AleXander)

Season Two
1. What's My Line, Pt. 1: Oz finally gets to meet Willow when both are selected by a major software company as potential employees. Later, in What's My Line, Pt. 2 he takes a bullet for her. Awwww..
2. Surprise: Oz and Willow have their first date, at Buffy's surprise party. Later, in Innocence, he helps the gang score weapons from the local army base, and explains to Willow why he's not going to kiss her yet.
3. Phases: Oz and Willow are dating, but there's still a noticeable lack of kissage. Willow confronts Oz, but he's a little preoccupied with his own problems- especially his new found attraction to the full moon.

Aside from the episodes listed, Oz makes breif appearences in: Inca Mummy Girl, Hallowe'en, Bewitched, Bothered & Bewildered, and Becoming Pt. 1.