Imouto Haramasenai to Level Up Dekinai Isekai Tensei

After dying in a traffic accident, a young man is reincarnated in a fantasy world where the only way to level up is to impregnate his little sister. He discovers that his new life comes with a bizarre and explicit condition that forces him into an incestuous relationship with his sibling in order to gain power and survive in this dangerous realm. As he navigates this strange world, he must confront the moral implications of his situation while trying to adapt to the rules of his new existence.