The dialog talks about the fake emperor and remains unfinished, like if the guy who was writing the diary had been killed.
In those screenshots :
We can see a diary that you can only access if you find the secret passage in the bottom of the screen, but of course, it's a part of the background.
A friend of mine successfully reinserted the original icon of the Earthquake magic and also the censured boss but don't have a clue at all about the ways that could be used to reinsert this dialog. An event which would occur when the player press the "B" button at this place? (so by using x/y values?). By inserting a NPC and make it invisible? Or is it just impossible to add this dialog in the game?
Of course, the text is in the rom (copy-paste from the american version) at 0x9CAA3 :
(Unfinished diary entry)</Text>
<Text> ...My cover's been blown... Some monster's using[NewLine]
the Emperor's body to</Text>
(Text suddenly stops)</Text>
<Player id='0x1'/><Text>:What does this mean?</Text>
Here's a savestate done with Snes 9x Geiger 1.43 in front of the diary with the U version of the rom if someone want to take a look at it : http://www.hiei-tf.fr/som-u-savestate.rar