Description
Iroe Genma, universally nicknamed "Nee-san" despite her short stature and also known to classmates as "Chibiko," leads her school's Model Club. An initial passion for plastic models is signaled by a model castle balanced on her head, though this interest wanes significantly over time.

Her personality manifests as vulgar, outrageous, and deliberately troublemaking. She craves the spotlight and habitually engineers chaotic situations involving club members. Her conduct is wildly disruptive: unleashing random acts like demeaning animals, inciting physical fights, and causing public disturbances, including reckless driving immediately after getting her license. Temporary or artificial animal-like features, such as a beak or ears, occasionally appear.

Her primary interactions target Model Club underclassmen Hazuki "Okappa" Okamoto and Makina "Makimaki" Sakamaki, whom she frequently provokes or pranks. She associates with classmates Sanada and Yuria Himekawa (who use "Chibiko") and cultivates unconventional relationships with school staff, including a 33-year-old teacher who addresses her as "Nee-san." She regularly joins twin students Uno and Sano in absurd activities.

Notable behaviors include a signature pattern of initiating trouble, confessing to orchestrating an extended prank framed as her "first love story," and participating in bizarre incidents like burning a haunted portrait of Johann Sebastian Bach. Her declining engagement with plastic models culminates in the Model Club's transformation into a Calligraphy Club, despite the series title remaining unchanged. Visually, her signature plastic model hat simplifies progressively until it resembles a basic cone.

She appears in scenarios featuring fourth-wall breaks, encountering characters who narrate directly to the reader, and participates in formula-breaking episodes detached from the main narrative. Official media provides no concrete information on her family background, academic performance, or significant long-term character development. Spin-off works like "MeMeMeMeMeMeMeMeMeMenhera..." and "Aoikokoro ga chikyū o waru" offer no additional details on her role or backstory.