Based on the erotic game by Softhouse-seal Grandee.

In 20XX, the humans are about to go extinct...

Since the ratio of men and women is now 1:10721, the authorities establish a new law, "Sex New Law", and issue a card called "Free Sex Licence". Once a man shows his card to a girl, he will be able to have sex with her soon. However, it doesn't work...

The authorities decide to issue a new license to break the deadlock...