"I suppose, I should thank you." Ruby speaks. "In your own idiotic way, you allowed me to obtain all seven books."
"Why... Why do you want the books?" You ask.
"Do not worry, my reasons are my own, and will bring no harm to you, or to either world.
"But! I have to return all seven books to Saphira or her world will!" You stop, because Ruby had begun to smile when you spoke Saphira's name. The smile for some reason made you uncomfortable, and your ears folded back on your head as your tail drooped.
"Ah yes, Saphira I much desire to see her again, as you see I have a bit of a debt to pay... You have no need to worry about her world, as I will take over as its savior from here."
Ruby takes a few steps back, and all the books begin to glow. You reconize this from when new spells appear, but something seems different. The books all float around Ruby, who holds her hands up into the air, and a new book appears. An eight book!
"The Book of Reality." Ruby speaks. "With it, comes the power to change an entire world, or even to destroy it. It has a lesser power though that I'm interested in, the ability to connect worlds."
Ruby holds the new book, as the other books float around her, and points one hand to the ceiling.
"Portal Junction!"
A ball of light fires off from Ruby's hand and flies into the ceiling. The ceiling seems to just vanish, revealing the sky above it, which has turned gray, and then clouds seemed to be forming a cyclone above the mansion. You felt as if at any moment you could be pulled up into the cyclone.
Then, Saphira herself appears in the center of the cyclone, and levitates down until she is standing between you and Ruby.
".... Ruby." She speaks. She knows Ruby?
Ruby smiles. "Long time no see sister, or is it Saphira, guardian of Tellus now?"
Saphira frowns. "What is it that you want?"
Ruby begins to speak. "Five years ago, you banished me from Tellus to this desolate excuse for a world."
"You practiced a forbidden form of magic." Saphira explained. "One that would lead to war if your experiments were successful."
"I did it for the benifit of our world... I accept though, that in my youth, I was naive to think such a power could be used for good, and for that I have accepted my punishment to live in this desolate place, and that I was stripped of my magic. However, today I have redeemed myself." Ruby gestures to the books floating around her. "Our world can not exist without these books that generate its magic. It will soon collapse. I have collected them, and for doing so I request a full pardon and to be allowed to enter Tellus once more. Saving the entire world, surely that is justfication to correct my banishment? After all, I am not asking for my magic back, but just to return home."
Ruby is taking credit for your work! Sure she may have saved your a few times, but you're the one who did all the work! Well most of it. You managed to get the Book of Time, Beast, and Body on your own. Then the Book of Mind was a joint effort. She had only pulled off getting the Book of Arcane and Myth.
".... I know, you did not do all the workd." Saphira speaks. "... But... Things have become desperate on our side.. I suppose, I have no choice but to agree."
The area inside the cyclone in the sky begins to glow, and you're quite certain this is the portal to Saphira's world. Saphira levitates back into the portal, and a few moments later, Ruby and the books are sucked in as well!