This might seem to be another Japanese exploitation flick. Japanese schoolgirl battles monster from the moon who wields a chainsaw. These elements are definitely in the film. And artistically so. But are not what the film (and I assume the source manga) are about.

The theme of the film is how to deal with feelings of loss, lack of self-worth, lack of significance. A shiftless student Yosuke is trying to recover from the death of a friend Noto. Yosuke steals meat more to do something than because he has to steal it. One night slacker Yosuke comes across Eri who spends her evenings trying to kill a chainsaw wielding monster who falls from the moon. He becomes Eri's helper in her odd quest.

Both Yosuke and Eri externalise their problems - is that running away from or part of dealing with it? Both Yosuke and Eri find a kind of answer in each other, Yosuke finds a purpose in helping Eri, Eri finds strength from Yosuke.

The key figure in the film is in a way Noto even though he's dead before the film begins. Noto lived his life to extremes, followed Achilles in a short life but a glorious one. Yosuke tries to emulate to outdo Noto but in the end only achieves moderate happiness. But perhaps moderate happiness is not that bad.