Charmed Ones? Whitelighters? I'm never going to become readjusted to this dimensional shifting business. I guess this is closer than that whole Avatar business. Or the foul mouthed army guy down the hall. Urgh.
Angel is definitely not a guardian of witches. He used to follow Buffy around and make mopey faces but now he mostly follows Cordelia around and does the same. He's a Champion, I think. That's what Cordelia said anyway.
And well, he gets a special pass because he's got a soul most of the time. Except when he doesn't. I'm not really sure how it works.