As night arrives the shadows of Koga fall on Iga and a new threat are available for our lusty vixens. From a torid sexual encounter Yatsurugi Shinobu's companion Mashiba Aya is infected with a parasitic bug and succumbs towards the will. Having the same insatiable urges, the identical tragedy is getting ready to happen to Kage Lena. The sole known antidote is stored deep within the labs with the Koga Institute and is the only thing that can save