And where exactly are you changing into a swimsuit? Inside your room?
The whole event for clothing wasn't made to put jacket on swimsuit

It's like you're trying to break the game

It's authors fault for letting you even get an option to put on jacket over swimsuit
I fixed the problem with Turta quest. I made a small fix for you.
#!UCgFEQDT!bvoXZqGdLjd5-Ft_WmDZDhCGISZg_VmxFxVt46mGzKQ
Copy the file inside the data folder and overwrite.
Start your game and load the game file.
Go one square down from the water bucket and press ENTER.
Then talk with the guy next to the bucket and it should work.
I'll update the full game/data links and changelog later.
EDIT:
So my guess is you wanted to walk naked around and then a choice opened to equip swimsuit and normal clothes and then you went to experiment and you got the error...
The problem is the author never fully made this function functional.
But since I think this could be a nice addition to the game I'll make it functional but I'll need some time for that.
And the Red/Rod Optium happens when you take a break of one month between translations. You forgot what terms you used and shit like that happens.
I should be Rod Opium so I fixed it.