AIKa

Plot
Tokyo has sunk into the ocean, along with most of the world, during a large-scale land subsidence. Aika Sumeragi is a salvager who works for a small company run by a father and daughter tandem. Alas, the company isn't exactly successful, and money is needed desperately. Thus, Aika accepts the very dangerous job of acquiring an artifact called Lagu for a hefty sum. The boss' daughter, Rion joins Aika on this particular mission, and the two set off.

Later on, Aika and Rion Aida are captured by Rudolf Hagen — an effeminate but oversexed man who wants Lagu and Aika (and just about every pretty girl) for himself. Hagen commands a huge battleship manned (or womanned, in this case) exclusively by droves of cute girls in mini-skirts (an example of what is often called "fanservice"). Alongside Hagen is his obsessive sister Neena, who is jealous of Aika, as well as another salvager named Gusto, who's also after Lagu and has a crush on Aika as well. When Aika's special bustier is activated, she becomes a Superhuman who can take on whole armies by herself.