Japanese-occupied Hong Kong, 100 yen, final "red-brown" series (1945). In my ancient edition of Pick it's listed as China - Military - Japanese Military issues - P# M30. As with most late-series Japanese wartime money, it's relatively cheap, even in high grade.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis