Answer:
I am the only thing that place today before yesterday. (one word)
I'm a ruler with 12 agents. Half of them work in the darkness. Who am I?
The 8 of us go forth and back to protect our king from a foes attack
I am always around you but often forgotten. I am pure and clean most time but occasionally rotten.
I may only be given but never bought. Sinners seek me but saints do not. (one word).
When is it bad luck to see a black cat?