Ever sense the Great siren war or, the first siren war, humanity was at the brink of extinction, but they found there hope, the wisdom cubes, with this cube, they turned ships into Kasen's, ships in the form of female humans, with powerful abilities to counter the Siren threat, humanity was saved and victories in the bloody war, these old and still young willed shipgirls were later replaced, but what happened the old ships, no reports say they were scrapped or turned to Museums, so what happened, and how there lives have been after the great Siren war.