The close-knit Toujo couple, Koji and Natsu, had been struggling with infertility for years. However, it was discovered that the cause was the husband's azoospermia. Out of guilt, the husband suggested a sperm bank, but the wife could not accept the idea of using sperm from a complete stranger. One day, when the husband invited his favorite subordinate, Ryohei, to their home... after the husband passed out drunk, the wife directly asked the subordinate for a "sperm donation." While firmly telling herself that this "is not an affair," their relationship transcends the framework of a mere "donation," evolving into something where complex emotions and desires intertwine. Amidst guilt and a sense of immorality, they shift from an "act for fertilization" to a "relationship where they desire each other"...
