This happened yesterday:
My launcher turned Japanese for some reason (as shown).
I clicked start game. Nothing popped up (interface).
I double clicked the launcher. Nothing popped up.
I double clicked the launcher again. "This launcher is already running" pops up.
I decided to leave it for now.
After a few hours passed by, I decided to try getting on again. Same problem.
I did it for every 2 hours in 1 day. No progress.

Today:
Hoping it was okay now.
I tried to get on. The same problem occurred.
Trying to search the solution in google. No results.

Side note:
I also tried restarting my pc (3 times).
And reinstalling the game (giving me the same launcher problem).
Help please?...

This is a rather common problem, but there's no official fix at the moment .-.
One of the moderators, Ringo Tarte, mentioned that launchers were getting rolled back. You can copy all your files into a backup file and replace the game files with the backup files (Delete, copy, paste) when the updates starts again. It should return to its normal state afterwards.

FoxFaeez wrote:double clicked the launcher again. "This launcher is already running" pops up.
I decided to leave it for now.

Still, if your "leave it for now" means "update doesn't move after a couple of hours", that would mean that this part of the problem and re-installing not working is a rarer issue. Do check your internet connection if the full package with updated patches is downloaded. As of now, the full file is 3.93 GB big in total. If you are missing any files, you may need to ask others to send you the specific ones you lack.

I don't really understand what you meant about the launcher.
And by "leave it for now" isn't about the update. It's about the game not launching/popping up.
I decide to leave it for a few hours before I open it up again.
I never opens even until now.
And I'm sure my internet connection is fine.
Other games are working fine, it's just Onigiri not working.

Ok sry for not being clear, I'll try rephrasing it.
1. The launcher is the exact program that pops out when you open Onigiri (like the one in your screenshot). It is a "prelude" to the main cilent.
2. The "leave it for now" part refers to leaving the launcher ^ exactly where it is and waiting for that updating bar (35%) to fill up. If the bar is not filled up, the game is still updating itself and you cannot open the main cilent aka game. Just checking if you left the launcher like that for 2 hours or more as that is what I understand with your post.

I understand number 1 now.
But number 2 is where you got it wrong.
My launcher isn't stuck at 35% lol.
I launch the game. (The update is already completed) Nothing pops up.
I tried again, nothing pops up. And again, launcher already running.
After a few hours later. I tried to launch the game again (The game is already updated). But same problem, no game interface or window.

Clearing the cache is one thing, but the simplest solution is to keep and use backup files because it ensures that these are clean and untouched and you don't have to figure out the hassle of cleaning which exact cache.

Once you start the Japanese launcher and enter the game, it'll start redownloading which means it's beginning to wipe out your en files and replace them with the jp ones and once it's done it'll cause an error because of the originally en client rejecting the new files.

Basically, it means you either reinstall the en client or utilize backup .pkg files.

I have the same problem with mines, so I just uninstalled it completely and now redownloading...