Player > Items > Magic > Obfuscated journal
An obfuscated journal is usually a book filled with about
250 pages of sturdy blank paper. Those who value secrecy
and portability use such tomes in place of other methods of
information storage that might be less secure.
Before you can write in an obfuscated journal, you must speak a word or phrase to the book as a standard action. If you don’t, the pages won’t hold any writing. If someone reads the journal without speaking the word or phrase you set, the words in the journal are an indecipherable jumble. You can also command the journal to erase all or part of the writing at a rate of 2 pages per round.
The journal also defends against some forms of magical tampering. Writing in the journal is magical and encoded, but a creature under the effects of true seeing can read it. Dispel magic can suppress the journal’s magic, causing the pages to appear blank and preventing it from being used in any way. An erase spell can erase the journal only after the proper command is spoken.