If you loved Guinea Pig Part 4: Devil Doctor Woman, try Stacy: Attack of the Schoolgirl Zombies
A bridge between a film you've already seen and one most people haven't. Here's what they share, and what the second one does that the first one doesn't.
You already loved

Guinea Pig Part 4: Devil Doctor Woman
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Stacy: Attack of the Schoolgirl Zombies
What they share
Theyboth carry the 3am cult mood tag, and they sit in Comedy / Horror territory. If that's the register that drew you to Guinea Pig Part 4: Devil Doctor Woman, the second film will land in a comparable space — through a different lens.
3am cult
What Stacy: Attack of the Schoolgirl Zombies is
Tokyo suburbs summer air thick with cicada hum. Teen girls infected become violent. A Naoyuki Tomomatsu zombie comedy.