Rowan

Shutting your eyes tightly you take a deep breath and hold it attempting to calm yourself. Once you've regained your composure you release the breath and give the book another look over trying to contain your excitement. You lose yourself in thought for a moment remembering how many times you wished throughout your life. Coming back to yourself you quickly erase the previous rule realizing how boring and unimaginative it was and begin to think of better rules. You jot down some quickly starting with some precautions not wanting to risk losing the key to paradise you've just acquired.

"Old Rule:: No rule written in this book is capable of negatively affect the owner of the book"

"Old Rule: The owner of The Rulebook has a perfect memory and retains all memories from before a change following a rule being written"

"Old Rule: I the current owner of this book who is now writing this rule am Immortal and have always owned this book"

"Old Rule: Only I, The Owner of the Rulebook can write inside of it"

"Old Rule: The Rulebook is incapable of being lost, stolen, or destroyed in any way and will always reappear to the owner along with a writing utensil capable of writing under any circumstances"

"Old Rule: The Owner of The Rulebook is unable to die by any means as well as being unable to be permanently injured or maimed and can not be kept bound against their will"

"Old Rule: The Owner of this book is capable of shapeshifting to any form they wish but will always be attractive in accordance with their tastes to the form chosen"

After heaving a deep relieved sigh finally able to relax, and while you know on some level this seems excessively paranoid you still feel justified having successfully prevented any potential "Monkey's Paw" situations from arising. Taking a sip of your tea you look around the cafe deciding whether or not to use your "new" power to fix the world as you see fit or to dive right into living out all your perverted fantasies...