Manami, the sole survivor of Angel of Darkness 2, is rushed to hospital where she slips into a deep sleep. A priest correctly suspects that the demon (now referred to as an Injuu) is inside Manami's body, but by the time he is able to confirm his theory, the creature has already moved on. As before, the tentacled beastie passes from host to host (by thrusting its slimy appendages into its victims' orifices), eventually ending up inside goody-goody schoolgirl Fumie, who does her best 'Linda Blair' impersonation for a while, before the priest inevitably turns up to save the day.
Sorry, but for now we weren't able to find movies like Angel of Darkness 3.