Continuation of the anime story.
Tayo is 15 years old and he's the owner of the ship that along with the six female crew is flying to explore ancient ruins. Fifteen years ago Tayo's family got attacked by pirate ship and he was the only one to survive in escape pod. The pod drifted to the Agga Ruter spaceship and Tayo was raised by its central system K3.
But at the same time at the other side of the universe the ruler of female alien civilization got tired playing with her subordinates and she set off into space as soon as her radar spotted a man she can play with - and that turned out to be Tayo.

[From vndbreview]