The island of the everlasting summer, Seiran Island.
 
Junnosuke Tachibana, who was born on this island, returns with his younger sister, Asane Tachibana, after the death of their parents.
 
However, Seiran Island has become a place of madness due to the implementation of the “Perverted Law,” a law designed to combat population decline. This law permits and even encourages lewd sex acts everywhere on the island, and refusing to engage in “reproductive activities” is punished almost as severely as a crime.
 
Junnosuke, a proud virgin and staunch defender of virginity, questions the legitimacy of this law. Determined to protect both his and his beloved sister’s purity, he forms the anti-copulation front NLNS (No Love No Sex) and sets out to destroy the Perveted Law once and for all.
 
“I’ll… destroy the Perverted Law!”
 
(Source: Official Site, translated)

Seiran Island is a place like no other, to deter emigration and attract tourism they have become the 'sex' destination as residents are punished if they are not have having frequent sex! On this crazy island, Hotori Misaki is still at school and one of the rare virgins trying to keep her secret and find love in such a lewd environment! 
 
Note: It was announced on October, 2021 that the publishing rights of the manga were acquired by Shueisha. The manga started being published on the Ultra Jump magazine since November 18, 2021.

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