"Your soul is like Heavy Rain. There is, or has been, a great sorrow in your life. Whether it be a death or other loss, you have powered through it and moved on with your life. Thus, I grant you my power." ― The Heavy Rain Gem
Blue Gem: Heavy Rain (青宝石: 大雨 [Ao Hōseki: Ōame - lit. Blue Jewel: Heavy Rain]) is a semi-common blue Gem used by Fuu Nairoga.