The decreasing birthrate becomes the major problem in 20XX. Especially, the number of men sharply decreases. To deal with it, the government sets up a new law called "Sex New Law". The law bans:

- from masturbating.
- from using contraception.
- girls from refusing when asked to have sex by boys.

Yasuhiro turns 20 today and he can now have sex with any girls freely. "I don't wanna have sex for my country. I just wanna have fun!"

[From ErogeShop]

The year is 20XX; an age where the world faces a population shrinkage crisis.
The birthrate of boys has dropped sharply and the adult males who support the country with their labour, steadily die out.
The government and related organizations are made up primarily of women in this age of female-dominance...
This a new law is proposed and enacted to correct the disparity of the male to female ratio in the government...the "Special Extreme Declining Population Countermeasure Law".
Our main character, Tsumura Yasuhiro was born in such an age and is the precious only male in the city.
Not only that, but today is his much anticipated 20th birthday, and he receieves authorization by the nation to freely conduct all the sexual activities he pleases...
Given the circumstants, what's a guy to do but violate every woman he sees??

[From English DLSite]