Protection is on the moment you install. Add a Keeper whenever you are ready, or not at all.
They see that protection went off, or that a device has been offline too long. They do not see what you read, where you went, or what you searched for.
You cannot weaken a boundary on your own, and when your Keeper changes one you see what changed and when.
Explicit images are covered on the pages you are already on. You lose the part you did not want.
Leaving a Keeper follows a set process rather than a switch, so it cannot happen in a moment of frustration or by someone else holding your phone.