If you loved Possessions, try Black★Rock Shooter
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.
What they share
Theysit in Animation / Fantasy territory. If that's the register that drew you to Possessions, the second film will land in a comparable space — through a different lens.
What Black★Rock Shooter is
Neon Genesis Evangelion if set in high school. Two young women find their bond tested as their inner turmoil manifests in a surreal, violent alternate dimension. The OVA is thin but the visual invention is strong.

