Hajime resides with twin sisters from the Komatsu shrine family. Inori possesses a deep spirituality and utilizes her cherished rosary to shield her loved ones from malevolent forces. Kanau is pragmatic and devotes her time to preventing Hajime's unintentional groping of women.
As bizarre murders, reminiscent of vampire attacks, plague their society, Hajime dreams of Satan, a seductive female demon coveting his blood. To his surprise, she and her persona, Lucifer, manifest in his reality. Following a mortifying incident at school, Hajime and the shrine twins elect to offer Satan/Lucifer refuge in their home. The question remains: why are these demons drawn to Hajime, and what sinister intentions do they harbor?
