Sengoku Koihime: Otome Kenran Sengoku Emaki (Manga)

is a Japanese manga series written by BaseSon and illustrated by Yukino Amagai. The manga was serialized in the Dengeki G's Comic magazine and published in Japan by ASCII Media Works under the Dengeki Comics NEXT imprint from December 2014. The manga is based on the Eroge franchise of the same name.

Synopsis
[Summary of Sengoku Koihime: Otome Kenran Sengoku Emaki - Versus!] This manga is based on the erotic game of the same name, which is part of the 'Koihime' franchise of erotic games. The main character, Nitta Kensuke, touches a sword in a storeroom one day and falls unconscious. When he wakes up, he is in the Sengoku ("warring states") period of Japan, except all the historical figures are sexy young girls and the country is under attack by human-eating, blood-drinking demons!

(Source: MangaHelpers)

Sengoku Koihime: Otome Kenran Sengoku Emaki - Versus!
A spin-off manga, written by BaseSon and illustrated by Kashi. It was serialised in Dengeki Daioh and released under the Dengeki Comics NEXT imprint from December 2014.