I just the fact that she likes a guy and isn't about to listen to any of the crap her 'peers' are spouting. It's a case of "Giles, you screwed my mother, twice. Yes I did hear about that. Spike, you screwed my sister and Harmony. Buffy you screwed not one but two vampires. Willow, you went black wicca. When you behave, you can tell me what to do."

Spike's about to get the surprise of his life when he's trying to glomp her proper and keeps on finding pointy implements hidden all over her :D Plus, she's got the standard Slayer uniform, whereby random bits of clothing are weapons - my favourite piece she's wearing is a belt made up of silver crosses all linked together (useful for throttling and toasting at once).

And she would definitely do that with his nails, because he has no idea where he can and can't touch her at this point without being scorched - all part of the charm, eh? :D