So this has happened a few times to me a few times now, the game won't start:
- after a fresh install
- after a recent maintenance/update

What to do:
- Right click the game from the list, go to local files, select all and press delete.
- Back to the game list, right click, go to properties, local files, verify integrity.

Essentially re-download the game. Why this works over a fresh install? beats me, but it works.

Now you're free to playwhale other gachas on your phone, while you waste away in Onmyoji.

Kyuu kyuu nyo ritsu ryo!