I have a new idea for who twilight may be, ( actually I have 2 )
One is that it is one of the knights from those knights that were trying to destroy Dawn - ( They obviously need a new hobby) or its Dracula's son Vlad 2nd.
I also think at some point she will have to battle a dragon, as she has had 2 dreams in this seirs about dragons.
I thinks its Glory.. I think Twilight's actually the first 'direct' big bad since Glory.Who seems to macth Glory identity ,strenght and so on ,we never know glory true identity ,so it could by a man in her dimension , we never now ..!
Well, Satsu does play the handsome Prince to Buffy's Sleeping Beauty in Long Way Home, but no, Satsu doesn't fit for Twilight.
Ethan Rayne references Hamlet, but not in a way you could see him as the Danish prince.
Speaking of Hamlet though...and this is no doubt reaching, in Lies My Parents Told Me Spike says "There's the rub, innit", a clear reference to Hamlet's famous To Be, or not To Be soliloquy - "Aye there's the rub".
The Oedipal thing has been discussed in referenced to both Hamlet, and Spike, and Oedipus was the prince of Thebes, I think.
And in The Gift Spike parodies the St. Crispin's speech of Prince Hal - "we few, we happy few".