Bleach is a very well-thought out metaphor for the immigration problems facing the United States. The series revolves around three main planes of existence, each with a real-world counterpart. Hueco Mundo is analogous to Mexico, the "real world" is analogous to the United States, and Soul Society represents the United States government. The beings from Hueco Mundo, known as Hollows, are the illegal immigrants who come in to the real world in search of food because their own home is a barren wasteland and desert. Unfortunately, they feast on human souls, much like real Mexicans, which causes Soul Society to despise them and force them to become proper citizens by purifying the Hollows with a zanpakuto, a process symbolic of acquiring legal citizenship. One rebellious man from Soul Society named Aizen is trying to give the illegal immigrants power and status as well as overthrow the corrupt Soul Society government only to be confronted by the main character, Ichigo, who has an internal conflict due to trying to stop the Hollows despite being half-Hollow, or half-Mexican himself.