TV-Series
Description
Karamatsu Matsuno is the second-eldest of the six Matsuno sextuplets. His name is derived from the Japanese word for the larch tree, and also carries a pun on kara, meaning "empty," a concept that has been used to describe various aspects of his character from its earliest iterations.

As a child in the original Osomatsu-kun, Karamatsu is depicted as a cheerful, carefree, and highly energetic boy. His energy is often described as coming from a place of bravado or an "empty spirit," which fuels his impulsive actions and a tendency to rush headlong into situations without considering the consequences. This recklessness frequently results in him getting injured, becoming the unlucky scapegoat of his brothers' misadventures, or leading another brother, often Todomatsu, into trouble alongside him. He shows a more vulnerable side as well, being somewhat of a crybaby and prone to running away in fear when genuinely threatened, as seen in a boxing match against a stronger opponent. Despite a noted lack of academic intelligence, he does display some practical and artistic skills, such as sewing a large stocking for a trap and showing an interest in painting. He also has a large appetite, once eating the family's entire daily supply of rice, which resulted in a severe stomachache.

During his teenage years, as depicted in the Osomatsu-san movie, Karamatsu's personality shifts. He becomes more subdued and timid, struggling with chronic acne and a worried, introverted demeanor. In this period, he wrestles with his own identity as an individual separate from his brothers and makes unsuccessful attempts to mediate the growing conflicts among them. A pivotal moment occurs when his future, adult self gives him a pair of sunglasses, accompanied by a false promise that he will eventually have a girlfriend. This interaction solidifies his path toward adopting an over-the-top, dramatic persona.

As an adult, Karamatsu cultivates a flamboyantly confident and charismatic public image. He believes himself to be exceptionally cool and popular, often referring to his hypothetical admirers as "Karamatsu Girls". He speaks in a drawn-out, poetic manner, frequently interjecting with random English or French words to enhance his desired effect. This persona is visually reinforced by his signature outfit, which typically consists of blue clothing, a black leather jacket adorned with a skull motif, tight jeans, and his most prized accessory, a pair of blue sunglasses. Despite the theatrical confidence, his attempts at being suave and cool are almost always met with failure and derision. His brothers frequently label him as "painful," and he is often ignored, dismissed, or even subjected to physical abuse by them. He is derogatorily referred to as Kusomatsu or "Shittymatsu," particularly by his younger brother, Ichimatsu.

Beneath this fabricated, charismatic exterior, Karamatsu is revealed to be quite timid and easily intimidated. When placed under any kind of pressure, his typically deep voice becomes noticeably higher, suggesting his confident baritone may be an affectation. His brothers dismiss his claims of being "the nicest person in the world" as an excuse for his lack of backbone, though his actions often show a genuine, if unappreciated, care for their well-being. He feels deep frustration over how he is treated, and has even broken down in tears about how his brothers' mockery makes him want to kill them at times. Despite this, he is incredibly resilient and consistently bounces back from humiliation, demonstrating a dedicated, if misguided, commitment to maintaining his self-image as a Casanova.

His role in the story is primarily that of prominent comic relief, a character whose inherently pathetic attempts to be impressive are a source of humor. His key relationships are defined by the largely one-sided affection he shows his brothers. His childhood bond with the youngest brother, Todomatsu, was particularly close, with the two often sharing adventures and misadventures. As adults, this specific pairing becomes less prominent. His relationship with Ichimatsu is notably hostile, as Ichimatsu consistently bullies him, destroying his possessions and physically attacking him. This animosity is suggested to stem from jealousy of Karamatsu's outward confidence, and it gradually softens after Karamatsu sacrifices his own reputation to protect Ichimatsu. Even so, Karamatsu largely remains oblivious to this deep-seated hostility, interpreting it as a unique form of brotherly love. Over the course of the later series, his character sees subtle development; his aggressive narcissism becomes more subdued as he is shown reading more, wearing his flashy clothes less often, and becoming more withdrawn, hinting at a possible decline in mental health or growing depression. Notable abilities include his aforementioned skills in sewing and painting, as well as playing the guitar, talents which are often overshadowed by his failed attempts at being cool.