I would assume Japan sinks under the weight of thousands of 600+ pound Demon Slayer weaboos in this scenario. Seriously, have you been to an anime/manga convention in the States? I'm surprised the women at these conventions could even stand and walk for the duration of the event! Meanwhile, Minnesota's landmass would finally rise to pierce the Heavens (Tengan Toppa GURREN Lagann!!) in this scenario, now that it only has to carry the weight of Japanese people that barely eat 500 calories a week. The only downside is that it would have to "carry that weight" for 100+ years per citizen--longer lifespans and all that.