Izumi is a twelve-year-old schoolgirl living in an unspecified city with two extraterrestrial maids who arrived unannounced to protect against monster invasions. Her life before their arrival remains unexplored.

She maintains a consistently taciturn and emotionally reserved demeanor, displaying minimal reaction to the maids' presence or their lewd and unconventional behavior, her expression unchanging. Her daily bicycle commute to school leads to an accident when the brakes fail, causing her to fall onto a giant lizard monster. Throughout this encounter, she remains passive as the creature interacts with her.

After the maids defeat the monster—revealing its true form as a weakened seal—Izumi joins the crowd encouraging it toward water. She later waves farewell to the seal alongside the maids. Her relationship with the extraterrestrial pair is marked by apparent tolerance rather than active engagement, with no observed shift in her demeanor during these events.

No further appearances or developments occur beyond this incident in documented media.