A World where Mercenary Men are Called Goddesses

Yuichiro, a 37-year-old freelance mercenary, was blown unconscious by a grenade during a guerrilla war and found himself in a strange world. In that world, princes are currently fighting for the throne, and civil war is brewing. It seems that Yuichiro was summoned as a "goddess" to save the boy who is the "rightful king" and save the country. He is an old man, and he's the goddess?! And in order to return to his original world, he has to give birth to the king's child?! Yuichiro is disgusted, but he decides to join the war in another world in exchange for money...