Beautiful Lyre

I am the prince of principalities
But evil I am not
I am the king of formalities
Yet lies fill my draught

Enter my manor of manners
Abysmal abode
Filled with peaceful planners
Horrors are stowed

My tongue is of the finest silk
Made to be taut
My eyes are like the whitest milk
A soul, surely not

Yes, I have many fiendish friends
A very pleasant lot
And now, here your story ends
I'll enact my master plot