Zettai Junshu - Season 1

Based on the erotic game by Softhouse-seal Grandee. In the near future, a severe decline in male births has pushed humanity toward extinction. A national law establishes the Free Sex Licence as a countermeasure to raise the overall birth rate. The bearer of this licence is legally entitled to present it to any woman, at any time or place, and she is obligated to comply with sexual intercourse. Takumi's life is altered completely when he obtains one of these licences. His encounters include Sara, a genius with a scholarly curiosity about sex, and Misaki, who is the older sister of his childhood friend Rin. Rin herself harbors secret feelings for Takumi and becomes deeply distressed by his activities. The situation escalates when Takumi accidentally reveals the licence within their classroom. This public exposure leads directly to Rin losing her virginity in front of others.