TV-Series
Description
Iyami is a long-running character in the Osomatsu franchise, originating from the original Osomatsu-kun manga as a side character and antagonist to the Matsuno sextuplets. His name is a pun on the Japanese word for disagreeable, gaudy, or unpleasant, which accurately reflects his core personality. Physically, Iyami is a tall and slender man with a pale complexion, narrow eyes, a thin black mustache, and a smooth bob haircut with a straight fringe. His most distinctive feature is his large protruding overbite, showcasing three prominent front teeth, which he is known to be very prideful of. He typically wears a flashy, tattered pinkish-purple suit with a red bow tie, though the bow tie is sometimes absent, and his socks are always loose and patched up.

Iyami's personality is a blend of childishness, vanity, and self-centered opportunism. He is a conman and a swindler by nature, constantly scheming to make money or obtain food through theft, lies, and various scams, which usually backfire on him. Despite his arrogance and flashy demeanor, he is often impoverished, homeless, and unhygienic, resorting to eating from trash bins to survive. He is a coward who frequently shifts blame to others but also possesses a surprisingly kind and naive side, capable of genuine acts of compassion and gratitude. While he is an irritating presence, he is not a born troublemaker in all contexts and sometimes even serves as a comedic straight man reacting to the bizarre antics of the sextuplets.

A central and defining aspect of Iyami's identity is his delusional obsession with France. He constantly claims to be from France or to have just returned from there, peppering his speech with French phrases like "bonjour" and insisting that his actions align with French customs. Evidence strongly suggests this is an affectation rooted in Francophilia and that he has likely never been to France. His ultimate stated motivation is to return to France, a goal he never achieves. His speech is also marked by other unique tics: he refers to himself as "me" or "moi," calls others "chimi," and ends most of his sentences with the suffix "zansu".

Iyami is best known for his iconic "Sheeh!" a vocalization and pose he strikes when shocked or surprised. The pose involves raising one arm in the air, placing the other across his chest, and springing one leg up at the knee, causing his loose sock to sway comically. This gesture became a popular trend in Japan and is his definitive trait. His laugh is often written as "uhyo~".

In the story, Iyami serves as a recurring antagonist and a self-proclaimed rival to the Matsuno sextuplets, particularly their leader, Osomatsu. He frequently schemes against them, but his plans are almost always thwarted, leading to his humiliation. His most significant relationship is with Chibita, a fellow oden vendor and former side character. The two are often partners in crime, plotting and scamming together, but Iyami also shows a genuine soft spot for Chibita, making him one of the few characters to receive Iyami's empathy and kindness. In some versions of the story, they are even depicted as cousins. Other key relationships include a rivalry with the scientist Dekapan and a sometimes inconsistent attraction to the beautiful Totoko.

Iyami's role has seen significant development across different adaptations. In the original and 1988 Osomatsu-kun anime, he and Chibita rose to become the main protagonists, sidelining the sextuplets. However, in the later series Mr. Osomatsu, he is relegated back to a supporting role within a large ensemble cast, often acting as a nuisance or a rival who is acutely self-aware of his status as a classic character. Despite his usually unpleasant nature, Iyami has moments of unexpected depth and development. One notable example is a storyline where he works himself to the brink of exhaustion and willingly serves jail time to make a blind little girl's dream come true. His family background is largely a mystery, though he has been inconsistently shown with an older brother, a mother, and a daughter who all share his prominent overbite.