Though Macoto Tezuka will forever be "the son of legendary...", he did manage to grow out of the shadow of his illustrious father. At the start of his directorial career, he spent most of his time making quirky, anime-like features, Monster Heaven is a perfect example. It's far from his best work, but if you're looking for something short and kooky, this is a pretty good fit.
The plot is pretty nonsensical, but that hardly matters. We're following a head scientist who is working with his team on some kind of hyperrealistic 3D CG projection system. One day he gets a document that outlines his family history. He learns that he is part of a long line of yokai hunters. Cue a bunch of yokai who will be making his life quite a bit harder.
The characters are familiar caricatures, the horror is played for giggles, and Tezuka has some fun with the costumes and cinematography. The pacing is snappy, the runtime is short, it's just that the film feels a little too flimsy and inconsequential. Tezuka never goes all out, and films like this need that extra bit of commitment and enthusiasm to truly shine. It's decent enough, but only if you appreciate this type of cheese.