Mizuhara Reito is an ordinary boy who wakes up in a world of 5 billion women and 5 men. Now it’s up to him to repopulate the human species. Can he stay loyal to his missing childhood friend when all humankind is counting on him to sleep with as many girls as possible?

As Reito begins to adapt to this new, man-less world, he finds clues that the virus was artificially created.

A bullied teenage boy wakes up in the future after going into cold sleep. His new high school is filled with nothing but girls, and more than a few of them seem to have an interest in him, especially his old teacher.

Shota continues to live his new life, in the school surrounded by girls. But not everything is as it seems ...

Reito learns that Mira has been replaced as his assistant. His group goes to the place where the first case of the virus occurred.

Reito finds clues leading to the origin of the MK virus. He also finds out that anybody who researches the origins of the virus tends to go missing quickly...

Shota continues his new life in school, but gets into trouble and thinks he is being treated like an object.

As Shouta becomes accustomed to life as the only boy at school, he starts to seek out more and darker thrills. And his keepers are more than happy to oblige his every need...

As a messenger from UW's global headquarters arrives in Japan, Reito finds the secret behind the creation of the MK virus.

The Numbers come under attack from terrorists calling themselves Izanami. But one of Izanami's leaders is the girl Reito's been searching for since he woke up.

As UW World Headquarters solidifies its control over Japan, Reito escapes to Taiwan, where he will finally reunite with his beloved childhood friend.