There, beneath your skin, above the stomach, between the lungs, below the heart, beside the blood. There it is. Don't touch it. At least, not until you know what it is.
It sleeps. It sleeps until its needed, when your brain sends that strange, secret message and it awakens, groggy and barely conscious, and that's when it performs its most powerful act. It may pull strings when it has struggled into full awakeness, but it can rearrange universes when it first opens its eyes inside of us. And sometimes, when it confusedly strikes, the universe is struck in the right place. But sometimes not. Sleepy eyes sometimes miss when asked to fire a shot.
It is not intentionally malignant, but it is not consistently benign.
If you try to reach inside and pluck it out, strike it from you, you are free to do so. There is no shame in living without that beast inside the body. But when you try to push the great, looming blocks that make up your life, then, when you are alone and dwarfed by the weight of these bricks, you may have a regret or two. The beast is dangerous, but it is strong, and even the most dangerous companion can prove its merit by the end.
Don't go looking for its lair in your bones. Don't go digging for its chain so as to let it loose upon the world. Everything in its own time.
It will wake up, soon enough.