What am I?

To be fair, I'll give you hints.

You may think me clever.

You may think me dull.

Depends on my contents.

This is what hold within.

Within me I hold the key to enteriung new worlds.

I can hold themes of darkness.

Or I can hold themes of love and wonder.

Within me I hold paper tattooed with words, held together by a sturdy spine.

You may find me completely in paper.

Or perhaps hardback.

Or maybe bound by thick leather.

What am I?

A book. A novel. A story.