There was once a man who was summoned to another world, and saved it. Of course, he became too popular there, and turned into an isekai-normie. However, that man fell into a "trap" and was forcibly returned to his original world. Moreover, he had to start over as a baby! This is the story of the way-too-fantastic ex-hero who lived as a gloomy high-schooler, as he gets summoned once again to that same other world in a very unexpected development!

Upon first seeing Earth from the Azatos Empire's survey ship, Chief Investigator Liza Luna plans to eradicate every lifeform on it immediately, leaving behind only useful resources. While surveying the planet, Liza discovers that human civilization has evolved at a pathetic rate compared to other lifeforms. Liza makes her way to the surface of the planet to properly inspect and understand its inhabitants. Still convinced that there is nothing beneficial to be found, the investigator makes her way into a cafe to gauge the planet's food culture. Liza walks into a cat cafe, where she meets creatures far cuter than anything else in the galaxy. Motivated by this new discovery, Liza decides to investigate Earth's numerous adorable inhabitants.

In the entertainment world, celebrities often show exaggerated versions of themselves to the public, concealing their true thoughts and struggles beneath elaborate lies. Fans buy into these fabrications, showering their idols with undying love and support, until something breaks the illusion. Sixteen-year-old rising star Ai Hoshino of pop idol group B Komachi has the world captivated; however, when she announces a hiatus due to health concerns, the news causes many to become worried. As a huge fan of Ai, gynecologist Gorou Amemiya cheers her on from his countryside medical practice, wishing he could meet her in person one day. His wish comes true when Ai shows up at his hospital—not sick, but pregnant with twins! While the doctor promises Ai to safely deliver her children, he wonders if this encounter with the idol will forever change the nature of his relationship with her.

After a successful showdown at Tokyo Tower, the Mew Mew girls enjoy a temporary respite. Now that Ichigo Momomiya and Masaya Aoyama have confessed their feelings to each other, Ichigo is overjoyed to spend time with her new boyfriend. However, their quick break gets interrupted, and soon the girls must battle against the Chimera Anima yet again. When things go awry in the ensuing fight, Ichigo is placed in grave danger. Just when things look most bleak, the mysterious Blue Knight arrives and saves Ichigo, proclaiming that he was born to protect her, before disappearing into thin air. With the fate of the world on their shoulders and the identity of the Blue Knight in question, the Mew Mew girls must strive to create balance between alien-fighting and their personal lives.