Vestal Claret three and three are six

Fashion myself an anti-Christian
In hopes to instil you all with fear
You this can tell by my attire
That uneasy feeling when I'm near
I do it all for the priestess, her approval I do bid
It's my only explanation for the evil things I did
You'll find them laying near the creek bed
The three young boys are down there dead
Naked, hands and feet behind their back tied
Bite marks across their crotch and hind
Black mass and sacrifice and witchcraft
Blood filled the orgies of the Esbat
Seeking the power through my first born
Let the child feed upon my scorn
I am the Devil for the host took
Drawn from the four stones and a foot
Heart of an unborn baby, human fat for me to fly
Gutted small vermin and a dog for me to dine
Black mass and sacrifice and witchcraft
Blood filled the orgies of the Esbat