That's what BaiBai gets for copy pasting shitty code and not debugging it.
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's where he seems to have gotten it from if anyone cares.
The problem is this system assumes the chat is always initialized by whoever the MC is texting. So, if the MC texts first, as is the case here, it crashes because some variables aren't initialized properly. Honestly, after a quick look I couldn't be bothered to fix this ugly ass code. Whoever coded this should be banned from ever producing any more python code, I swear. Who the fuck codes like this, jfc.
For a quick fix, go to line 6649 in the file d5.rpy, which should be an empty line, and add the following:
Make sure indentation lines up properly.
What it does: It adds an empty text sent by the person MC is texting, in this case Catherine, so that the problem mentioned above is circumvented.
If the same error shows up later when texting Aden, add
in line ~8500. I don't know if it's necessary here, but just in case. I haven't really tested whether it crashes here as well.
Here's the file with both of these in place
with Joker's mod. If you're not using the mod already don't download this file. Or download it and don't complain to me if something breaks.