I found this one while looking for Japanese homebrew. The last update was 08/12/24 so it's an old game. I Couldn't see it posted on any English sites so this might be the first time a lot of people have seen it.
It's basically a simple brain training maths game with a weird set of rules. You're supposed to touch the wrong answer, except if the answer is 9, then you click 9. See the video link below.
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