Akito Terada was an ordinary office worker, but he possessed a unique physical trait: his injuries healed at an abnormally fast rate. One day, he was contacted by a sperm bank through connections from his grandfather, a genetic researcher. Years ago, his grandfather had examined Akito’s body— analyzing his blood, cells, and sperm—and discovered that, in addition to his rapid healing, he carried genes that made him exceptionally likely to cause pregnancy. Upon learning this, Akito developed a trauma, fearing that having sex would inevitably result in pregnancy... Yet, the sperm bank, aware of this trait, asked him to provide a donation. Although initially suspicious of such a dubious-sounding offer, he decided to accept the request—despite the outrageous conditions requiring the recipient to be a woman under thirty and the donation to be made solely through direct intercourse. Then, a few days later, the request actually came through...