Inside the context of the Giantess School Council there are various girls (and even boys) including leaders or presidents who the role is to patrol or simulate entire worlds or regions to secure the presence and imposing of like-deity duties over humans, usually causing drastic measures like using their powers to grow or teleport... Both of them are Sora and Umi, both slibings of a supposed unthinkable in power levels family has quite different personalities but with same objectives in the GSC, Sora being the hero-complex girl that acts like an idol but also a protector with the weakness to be quite sadistic sometimes or protectful, meanwhile Umi is the mesugaki girl that will be very mean on her giantess duties and will play or have quite complicated situations with her little sister Sora.