Agaha is the descendant of a ninja clan, entrusted for generations with protecting Cosmo, Earth's energy source. Currently serving as an agent for the Federal Investigation Agency, she has continued to battle the demonic fiends known as Youkai. However, the Youkai have developed a radar capable of detecting Cosmo's energy waves, aiming to seize control over it. Agaha managed to steal this radar, prompting the Youkai to launch a counter-operation—using Cosmo's resonance to lure out agents from the Federal Investigation Agency. Driven by her deep connection to Cosmo, Agaha falls directly into their trap. Immobilized by the dark ninja Kumoayakashi's web threads and poison attacks, she is rendered helpless, bringing the battle to a swift end.