Slytherin: I think Another Bag of Bricks by Flogging Molly really sets up the story of Slytherin (At least to me)
T`was in the early evenin`
Near the presence of the moon
You told me you would meet me here
Well now is not too soon
This dagger twisting in my back
Tells me I never should
Have trusted everything to fall
From beggar to fool
I see your face like every race
A serpent with two arms
Devouring me while rains the sun
With dreams in foreign lands
This cold dark tormented hell
Is all I`ll ever know
So when you get to heaven
May the devil be the judge
With another bag of bricks

I scratch your name across these walls
And with my blood turns red
Then drips upon my killing floor
Where I now call my bed
No precious light to harbor
Like so many here before
Now breathes a thousand more
With another bag of bricks