The "fraud" part would depend on what Japan's legislation says about endownments between unrelated parties. Many countries have similar laws about tracking transactions of expensive jewlery and precious metals and it's not fraud to buy for someone else (the point being, to track suspicious activity). The problem could be in how exchanging money and the bought product are treated. Most of the time both would be considered endownements and above a certain value threshold, they would require paying tax on them. Most countries exempt people from that if they are closely related (still require reporting it), but this is not the case here, so unless they paid the piper twice here (if the mentioned threshold was exceeded), they could be doing tax evasion

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Now that I think about it, since the foxes don't have proper legal identity (why else would they not do such transactions themselves?), they technically aren't even citizens, so it's definetly shady activity. So yeah, Goro-chan can absolutely be hauled off if he does this on a regular basis. Try explaining that

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