In a distant future where the sun no longer shines, Toshiro Kamiya gives up his body to a sinister floral metamorphosis for a payday. The earth of the distant future is covered in thick clouds, and the sun no longer shines. Plants wither, and oxygen is thin. To fight extinction, humankind has developed a technology that turns humans into plants, providing a small amount of oxygen. Is this process sustainable? Is it ethical? Toshiro Kamiya...