Oujou Giwa no Imi wo Shire!

Ichimatsu Kairo's former girlfriend, Kusakabe Hiyori, reappears after vanishing seven years earlier. Her sudden return disrupts his life, as he had become consumed by a fanatical devotion to a religion centered around her. Hiyori makes a bizarre request, asking for his sperm so she can have a child and have the process documented.