Tetsuro Tanaka, a lackluster and dim boy, is transferred to Gokoh Academy full of high expectations. However, expectations fade with a bad premonition the moment he steps onto the campus and finds all the students except him are girls! Wow! Its Heaven! Hes a prince surrounded by pretty maidens! Wrong! A series of weird and frightening incidents fall upon him. Then, 6 charming girls who are called Koi Koi Seven appear as his guardians.

The new school term has just started. Freshmen enter the campus a bit tense but very excited. Yuki, a fifteen year old girl, is watched and envied by everyone because of her beauty. Although she does not show it, deep down, she enjoys being the center of attention. However, all is not perfect with Yuki as she failed to get the top score on the entrance examination. She feels animosity toward Arima, whose score was the best of all the students.

A long, long time ago, in the Far West, there was a world called Paradise. This was the origin of civilization and faith, where humans and evil spirits coexisted in peaceful harmony. Suddenly, by a negative spiritual wave spreading over this world, the evil spirits and monsters become violent and begin attacking the humans. Ordered by the Celestial Heavens, a priest named Sanzo recruits his old comrades and sets out for the journey toward Indara in the faraway West to find the culprit behind this disaster