My cover does not belie my contents

My book cover will tell you everything about me and nothing at all.  What you think you see is not what's actually there. 

At first glance, I look young, bubbly, carefree, and reasonably attractive. 

Look closer.  You will see the scars on my skin.  Some caused by outside forces, some self-inflicted.  You will see the tragedies I hide behind a well crafted smirk.  You will hear the music of my soul etched into the coloring of my eyes, much like a record.  Blue-slow, gray-melancholy, purple-dark base notes (like bruises that never quite heal), yellow flecks-softly tinkling in the higher registers (sunlight peeking through rain clouds).

Open me and look inside.  I am nothing like my cover.  The contents look about 200 years older, and blacker than that deepest recesses of space.  I never let it out so it just stays beneath the surface.  Like liquid mercury.  Metallic and bitter, in an eternal ebb and flow.  Occasionally being drawn near to the surface but immediately pushed down.  Shine a light through my skin, you will see it all. 

I control it.  This much I have mastered.  I nearly lost it once to that Russian game that everyone talks about, but no one really wants to play.  I wish I could say I won, but truth be told the moment you decide to play, you have lost. 

The outside does not reflect the waters within, it has merely been constructed in a fashion to keep them from getting to you.