I'm dangerous for you

There's just so much I could do for you,
and so many ways I could also harm you.

I could be your shield and spare,
but I may also be used against you.

No matter what you say,
no matter what you do,
I simply know it...
I'm dangerous for you,
And dangerous, for you.

There's just so much I could do for you,
and so many ways I could also harm you,
but I would never forgive me if I did so...

So, we may never even begin;
Let's just turn over now...
Let's end before we start.