TFPT#1

In the place dark and lonely enough.
(Close your eyes, as this will be tough)
The place where none can come,
you find it being invaded by some.
The one who causes you the terrible pain,
and binds you with the invisible chain. 

And, Lo! there is she.

Quite oblivious of your presence.
(her smile will be your's life essence)
But O'! hold! for that place was lonely,
you must live there, and you only.
How did She occupy that space?
Building there herself a base.

And now, you have a reason to panic.

You saw the who was the invader.
(A river of blood and that ruthless crusader)
By now, you know whom you chose
and granted permission to be so close.
This experience will be brutally rough,
as you remember, the place was lonely enough.

P.S. - You die when she stops being happy.