And to me, Whistler was always a mentor from the Powers That Be
Really?
Buffy: What are you, just some immortal demon sent down to even the score between good and evil?
Whistler: Wow. Good guess.
Whistler: A demon... technically. I mean, I'm not a bad guy. Not all demons are dedicated to the destruction of all life.
So, he's an immortal demon... sent to settle the score.
For which side? Good and Evil are a balance. Not supposed to have a clear winner - bad for business.
Whistler: 'Cause you could go either way here.
Angel: I don't understand you.
Whistler:
Nobody understands me. That's my curse.
Angel: Whadaya mean, I can go either way?
Whistler: I mean that you can become an even more useless rodent than you already are, or you can become someone.
Key figure of predestined "The Apocalypse" scrounging for rats the remainder of his unlife - that is indeed useless.
Whistler: But I thought he [Angel] was here to *stop* Acathla, not to bring him forth.
Talk about your missed-insider information.
And a burning question is; what did this have to do with Buffy and why Whistler showed Angel when she was approached by her first Watcher?
According to prophecy, she was destined to die at the hands of the Master.
Whistler: She must be prettier than the last Slayer. This isn't gonna be easy.
The more you live in this world, the more you see how apart from it you really are.
Last Slayer? WTF does the last Slayer have to do with anything here? Really?
Is there some other subtext going on here? Is Angel supposed to be involved with the literal "Last Slayer" who obviously would not be Buffy?
Understand Whistler - not! Curses! There's something afoot here and I don't think it's kosher. And what exactly
isn't going to be easy?
So, the more involved he becomes in the world the greater the clarity that he just doesn't fit in it.
Interesting and when realized, sobering and possibly even depressing for Angel.
Funny thing is, Angelus was the only one of the bunch without humanity and deemed worthy that really could bring Acathla forth.
Dru may have heard it whispering, but I doubt she would have been able to release it.
So if Angel was left to roam for rats, no Acathla to open vortex.
I'm not so sure Whistler was a mentor in the sense you meant.