主人公・新田剣丞が現代より転移したのは戦国乱世真っ只中、 ”鬼”の蔓延る、日の本と呼ばれる地だった。 天下布武を謳う織田信長をはじめ、名だたる英傑たちとの出会い。 恋に戦に絆を深めながら、列島全土で繰り返される数多の合戦。 戦友の死を乗り越え、試される覚悟と矜持。 鬼のいない太平の世を創るため「日の本連合」を結成する剣丞と仲間たち。 ――だが、 更なる災厄 が顕現する。 日の本全てを劫火で焼き尽くさんとする、 異史より現れし存在、”波旬”。 今こそ試される、真なる勇気! 今度の戦場は霊場の国、四国! 鬼若子・長曾我部 元親と共に黒鬼に立ち向かえ! 轟く渦潮は反撃の鯨波――

The Mori clan, the powerhouse of the Chugoku region, has finally begun to march towards Kyoto. Unless they can defeat Motonari Mori, who is a fierce enemy of Kuon, the alliance has no future. In addition to the Mori clan's powerful navy, the wisdom of Motonari, who seems to be able to read the future, overwhelms even Shino and Shizuku, and the teamwork of the three sisters, Mori Takamoto, Yoshikawa Motoharu and Kobayakawa Takakage, boasts a fighting force that surpasses that of Ayana and Konayayuki. Kensuke and his friends are forced into a tough battle like never before as a formidable enemy stands in their way like a giant wave. The biggest naval battle in "Sengoku † Koihime" begins on the raging seas!

Kensuke trained hard every day under the tutelage of his uncle Kazuto. One day, when he held a sword he found in the storehouse, he lost consciousness. When he came to, he found himself in a place he did not recognize. He met a girl who introduced herself as Oda Saburou Kuon Nobunaga. She held out her hand to a stunned Kensuke and asked him to become her husband and accompany her on the road to national supremacy. They travelled across the country, racking up victories in this period of social upheaval. However, there was one enemy they could not defeat: the oni. These man-eating, blood-drinking beasts soon took over all of Japan, plunging the country into hell. However, Kuon and Kensuke vowed to continue fighting, issuing a written appeal to all the influential lords: “Samurai who are not afraid of even the oni, gather under me and let us save Japan together!” [From [url=http://omochikaeri.wordpress.com/2013/12/01/december-2013-eroge-releases/]Hau~ Omochikaeri![/url]]