The final scene of this episode pretty much sums up what I love about it:
Willow: "Malcolm. Moloch. Whatever he's called. The one boy that's really liked me and he's a demon robot. What does that say about me?"
Buffy: "Doesn't say anything about you."
Willow: "I mean, I thought I was really falling..."
Buffy: "Hey, did you forget? The one boy I've had the hots for since I moved here? Turned out to be a vampire."
Xander: "Right, and the teacher I had a crush on? Giant preying mantis."
Willow: "That's true."
Xander: "That's life on the Hellmouth."
Buffy: "Let's face it. None of us are ever gonna have a happy, normal relationship."
Xander: "We're doomed!"
(everyone laughs then everyone goes silent)
And that's kinda what Buffy is all about really - the awkwardness of high school, and well, my life, where nothing ever seems to come off just right and everybody else is having the life that you kinda want.
But for me, the main plot is a side issue. I feel bad for Willow that this is the most attention she's ever received from a boy and that maybe that is the reason she is so easily caught off guard by this demon. But ... the rest of this plot is kinda ... yawn ... after the first time you see it.
To me, this episode is all about Miss Calendar! Who rocks! It's about time that another adult joins the circle - it was getting a bit creepy with Giles hanging out mainly with our trio in all his spare time. Surely he needs adult conversation once in a while? Like, about taxes or whatever. And the coolest scene is where he gets up the courage to stammer "there's a demon in the internet" and she calmly looks back, unblinking, and replies "I know". Plus, she's kinda hot.
Of course, her own background story, which is soon to be revealed, does dampen the impact of her being all wiccan and down with the hellmouth and all that on subsequent viewings.