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.

A crazy old woman steals what looks like all-butter shortbread from three statues wearing red hats. This causes an earthquake which releases ancient demon spores from a cave into a nearby pool of water. Unfortunately, this pool is precisely where a lesbian professor—part of a group of students and teachers who are spending a few days camping in the woods—decides to refill her water canteen. She accidentally ingests the spores, which causes the eruption of huge, thrashing, veiny, slime-covered tentacles that seek out new victims and enter the nearest orifice, thus allowing the demon to pass from host to host.

Ooshima Shino is a 1st-grade high school student. She has difficulties pronouncing words that start with vowels in front of people. Because of her speech impediment, she does not get along with others. Shino meets Kayo who likes music, but she is tone-deaf. They decide to start a band and Shino begins to change.

Mitsuhiko, an assistant director, has an experience with a young call girl at a hotel one day. He enters into a "relationship" with the girl he meets there for 30,000 yen per intimate encounter, but gradually finds himself being manipulated by her.

Five female college students, including Mana Kagawa, go for a drive but get lost in a secluded mountain village. The villagers welcome them warmly, and the five decide to stay the night. Their bodies are bursting with liberation. However, the next morning, Akemi is nowhere to be found. Then, Sayuri, who went to look for Akemi, also goes missing... Imprisonment, rope bondage, torture, lynching—one evil force after another attacks them. Who is behind it all...?