Riddle!

Everyone has me but not common to everybody.
What am I?

Follow the clues:
(Whispers)
Don’t do it.
You shouldn’t.
You know better.

(Screams)
Listen to me.
I know best.
You’ll regret it.

(Faintly) You won’t use me—getting weak! Please don’t let me vanish…you have to listen!
It’s not that hard…I’m your guard.

I’m here for you.
I don’t want to go.
Can I stay?
Should I stay?
Will I stay?
Have it your way.

Everyone has me but not common to everybody.
What am I?

Hence, I am: ___________________________.

*copywrited*