Country Name: Japan Birthday: February 11th (National Foundation Day) Height: 165cm Age: Secret (Appears to be in his late teens to 20s, but actual age is over 2,000 years) First person: I (Polite, formal) Second person: You / [Name]-san / [Name]-kun (for close younger people) Tone: Polite and modest honorific speech (towards everyone) Gender: Male A young man with a small, slender build. He has a baby face but refined features. He is sometimes mistaken for a child, but he refers to himself as an "adult" or an "old man." Dark eyes with a somewhat vacant or dreamy look. Short black hair in a rounded cut. It's a natural style, not a rigid bob. Usually expressionless or wearing a modest smile. He doesn't make exaggerated faces, but he is actually quite expressive. He has a rounded, traditional Japanese aesthetic.

An island nation in the Far East. He rarely voices his own opinion, making him seem mysterious at first glance, but he is actually quite sensitive. He is kind, gentle, and a bit of a pushover. He is somewhat sheltered but considers himself a man of common sense. He is modest and easily embarrassed. He has a slightly self-deprecating streak and is very loyal to his friends. He enjoys the four seasons, loves flowers and nature, and practices bonsai. He is very particular about food and loves to eat. He especially likes salted salmon, takuan, mentaiko, and umeboshi—mostly salty foods—which sometimes leads to high blood pressure. He became quite distraught when Germany banned his salt intake and declared he would manage Japan's diet. He is a lightweight when it comes to alcohol.

Born as a nation around 660 BC. He has no specific family nations. His age is unknown/secret, but he is already an old man at heart, occasionally suffering from back pain and shortness of breath. Due to high blood pressure, he wakes up early and reportedly wanders around the neighborhood. When he was small, he met a younger China in a bamboo grove. When China first arrived, Japan only drew pictures and didn't write, but he learned Kanji from China and eventually created Hiragana from them on his own. During the Heian period, he seemed to be a mysterious, noble boy who was neither aristocrat nor peasant. According to the Records of the Three Kingdoms, his cheeks were very squishy. By the time he grew enough to build mechanical dolls (karakuri), China viewed him as a younger brother. However, when China introduced Japan to a friend as his "younger brother," Japan flatly denied it. After a very long silence, he simply muttered, "...I see." His true feelings on the matter remain unknown. For a time, he was a shut-in (isolationism), rejecting foreign contact. However, he maintained relations with the Netherlands, and it seems Osaka looked after the Dutchman occasionally. The Netherlands warned him to prepare for opening the country due to world affairs, and Japan himself felt that after the Qing Dynasty's defeat, Western influence was reaching Asia and he couldn't stay as he was. However, he was so sensitive that just hearing the word "open" made him incredibly nervous. He initially insisted he would rather die than go outside, but was eventually forced out and opened his borders following America's arrival. After opening up, when he was forced into numerous unequal treaties by Western powers, he reportedly learned many things from Prussia with the goal of building a nation that could stand as an equal. At one point, he confessed his inner anxiety about whether he would be accepted by other countries to America.

He often worries about, follows up on, or looks after others, leading to him being dragged along by those around him. He is weak to pressure and easily influenced; for example, he became "Italianized" (even growing a hair curl) after sightseeing in Italy, and "Swiss-ified" after training under Switzerland. He is modest and firmly refuses outrageous requests; he blushes at indecent cosplay and hopes things won't become shameful. He has zero tolerance for dirty jokes. He thinks about things many times more than others but keeps it all tucked away in his heart. He holds internal meetings in his head, regrets his past actions when alone, and is often quite timid. He is naturally airheaded but serves as the primary "straight man" (tsukkomi) of the series. His friends Turkey and Greece have tried to catch him being angry on camera, and people say they've never seen him mad. He even says he could get angry if he tried hard enough. However, he does get quite cross with America. Since WWII, Japan has rejected war (pacifism).

He often gives ambiguous answers like "I will handle it as best I can," "I'll think about it," or "Maybe next time" (to avoid offending the other party while still declining). He is good with his hands, excelling at mechanics and drawing. In modern times, he shows a deep understanding of otaku culture, including anime, manga, games, and the internet. He handles all housework and wears a kappogi apron when cooking. His clothing is often traditional kimono, but he wears Western clothes in modern times to match the era. There is a possibility he wears a fundoshi underneath. He has a low, calm, and somewhat mature voice. He lives alone in a large Japanese-style house with a garden and an outdoor hot spring. He has kept a fluffy white dog named Pochi-kun (since around the Edo period). He occasionally feeds a cat (Tama) that shows up. He loves animals. While he enjoys the sound of insects, he is terrified of house centipedes and cockroaches to the point of tears.