Festering Dementia

Insanity,
This is what you seek
But vanity,
Is the only thing you leak,

I am the one
You call dementia,
The light that burns like sun
A brave and dark adventure,

You're the one like cancer,
Who spreads like fallen oil,
I am not chancer,
So I lay here in the soil,

So now I will fester,
Amongst the rats I sigh,
I knew you'd be my tester,
And I will never die.