Setting: At first in a grassy plain, then it changes to a ruined city.
Point of view: First person, he makes the audience sympathize with him.
Conflict: The first person vs. the jellyfish thing?
Climax: The first person and his later partner girl varmint? are living in the body that the jellyfish owns.
Symbol: Jellyfish itself: the world itself, and the obsolete city stands for the hidden and dreadful situation that secretly surrounds us.
Irony: When the branch the first person takes from a tree bears something gleaming white: jellyfish that will hold the protagonist in itself.
Theme: I couldn't figure out what all the circumstances specifically mean, but the substance of this story may be "sympathy with someone helps not him or her, but you(nasake ha hito no tame narazu) ." After the protagonist saved the plant, it seemed that the jellyfish born from the plant saved back the varmint. And then the protagonist can go on his field research.
