Priest Franz:
Whoever acquires enough Seal Stones will have the ability to control the Seven Seals.
That's especially true for those who learned how to control the Seal through the book found in Tower of Insolence.
That's why, in fact, the priests of Dawn and Dusk pay adventurers to collect Seal Stones.
Now, if you're correct, the mysterious manuscript you found is a copy of the Book of Seals, which contains the secret for completely controlling the Seal Stones.
Wait... What's this?! There's a strange energy around us. Shh!! Quiet!!!
Look around.