Made ¥10,000,000 last night, expecting to go multiples higher; tax question

I don’t personally recommend anyone to do the degeneracy I’m doing unless you’re in a comfortable state financially, but I have profited handsomely from a penny stock bet.

YTD I have roughly ¥2,200,000 in realized capital gains and it fluctuates but right now around ¥8,200,000 in unrealized capital gains.

I expect this to go much higher, but that’s a wait and see situation.

My actual income YTD is roughly ¥1,600,000. I got ¥500,000 or so from Japanese unemployment insurance from being laid off. My NHI payments are negligible now, like ¥350 a month because I was involuntarily unemployed.

So on paper, looks great. I’ve minimized my tax as much as possible. I’m going to pay a little extra to Uncle Sam because of short term capital gains, but that’s it. However, starting next April(?) if I’m still on NHI I expect my bill to skyrocket once I declare ¥10,000,000+ in capital gains.

A few ways around that are: find a new job that offers Shakai Hoken? I’m working on this.

If I can’t I think this might be a case where using my own company to pay a minimal salary to enroll in Shakai Hoken and avoid NHI might make sense.

Does anyone know what the numbers for this could be??

Thanks 🙏