In the future — in a world mostly submerged under water — the 19-year-old Sumeragi Aika goes to college while training as an agent by assisting in Aida Gozo's salvaging business.
Sumeragi Aika (voice)
E.T.A.I. (voice)
Shinkai Eri (voice)
Shirakiku Rin (voice)
Minamino Karen (voice)
Gozo Aida (voice)
Shiraishi Kana (voice)
Nagisa Risako (voice)
