That's a good point. I'm not aware of any rules I am breaking, I do hope I wouldn't get instadeported over a disagreement. If this becomes more popular I would start studying the formalities more.

I would recommend just getting a Japanese lawyer who is more aware of this stuff and pay him to make it legal. Reading through the laws is difficult, even if you read the language fluently.

And I don't think Japanese officials would consider this a "disagreement", but more like "illegal activity to avoid taxes". Which would involve a fine and being deported, as any other crime would.