Ikura is a lazy child who, alongside companions Maguro and Tamago, deeply admires a fictional superhero television show featuring elite warriors called Sushi Ninjas. While dreaming of emulating these heroes, Ikura and their friends consistently fail to exhibit heroic qualities in daily life. Their circumstances shift dramatically when encountering a princess pursued by the Nachos King Gang. Mistaking the trio for the actual Sushi Ninja television heroes, the princess urgently requests their aid. This mistaken identity prompts Ikura to join the impromptu mission to protect her.

Ikura embarks with their companions on a quest across the realm of Galaxy to locate the "seasonings of happiness," artifacts essential for resurrecting the fallen Sushi Ninja Empire. This journey marks Ikura's transition from passive admiration of heroism to active participation in a consequential adventure. Confronting adversaries like the Nachos King Gang, Ikura strives to fulfill the princess's expectations. Their development centers on transforming aspirational hero worship into genuine capability under pressure, navigating the gap between their self-perception as ordinary individuals and the princess's belief in their heroic potential.