North Korea's red, white, and blue flag flutters on the campus, signs are written in Hangul, and female students stroll through the corridors wearing the traditional jeogori costume. Professors lecture beneath iconic portraits of the father-and-son hereditary dictatorship that has run the reclusive Stalinist state since 1948.
Roughly 800 miles from Pyongyang, in Tokyo's leafy western suburbs, Korea University is an anomaly, an intellectual oasis in a society that distrusts and even despises the ethnic group it caters for: Koreans loyal to Pyongyang.
Part of a network of educational institutions established decades ago to serve the Korean population here, its students wrestle with politics and computer science but also the philosophy of the North's leader, Kim Jong-il. Surrounded by one of the planet's most hi-tech cities, undergraduates spend their entire four years in spartan on-campus dorms designed to encourage collective identity.
"Part of what we do here is protect our culture," explains the institution's president, Chang Byong-tai. "Our country and our identity were stolen from us by Japan."
But over half a century since it was set up, this university, like many of the cogs in the Korean network in Japan, is struggling to survive.
Hit hard by the decline in Japan's Korean population, enrolment has plummeted to just 800 students, down from 1,500 in the mid-1990s. Student fees pay for 70 per cent of the institution's costs; cash from Pyongyang, once a lifeline, has dried up to a thin, unreliable trickle. The institution has never received financial support or even official recognition from the government of Japan.
Mostly left alone for decades by Japan's authorities, the institution, like any with connections to North Korea here, has recently become a political punchbag. Ultra-rightists have driven up this quiet cul-de-sac and blasted the campus with anti-Pyongyang slogans from loudspeakers. Ethnic Korean children in Japan have been bullied and attacked. Thousands of Koreans are abandoning their ethnic identities to take Japanese citizenship and assimilate rather than remain as – in the words of one sociologist – Japan's "undigested others".
"The atmosphere now is very, very bad," said Kim Yang-Sun, an administrator at the university. Like most of the staff here, Mr Kim resents the attention, which comes on the back of growing tensions between Tokyo and Pyongyang and what he sees as unfair treatment by the authorities.
Mr Kim's ancestors have been in Japan since its annexation of the Korean peninsula in 1910. When occupation ended in 1945, about 700,000 Koreans stayed on rather than return to their homeland, which was then sliding into a war that would eventually split the country into two bitterly opposed states. Among them was the beautiful dancer Ko Yong-hui, who was born in Osaka, Japan, emigrated to North Korean and married its leader Kim Jong-il. She is the mother of the North's heir apparent and Kim's youngest son, Kim Jong-un.
When Tokyo normalised relations with South Korea in 1965, Koreans in Japan had to choose an administrative category, either as a South Korean with permanent residency, or to become de facto North Koreans. Most declined South Korean citizenship – which is ironic given that the vast majority originates from the geographic south. South Korea was then a poor dictatorship backed by the United States, while North Korea, though offering little freedom, at least boasted the rhetoric of a "workers' state".
"Koreans in Japan were very poor and had no civil rights, so it was a big deal that there was a nation that regarded them as compatriots, that gave them help," said Sonia Ryang, a professor of anthropology and director of the Centre for Asian and Pacific Studies at the University of Iowa. "The schools do an amazing job of maintaining Korean culture in a hostile environment."
Today, the grandchildren of those first-generation Koreans struggle with profound identity issues. Many distrust the Kim Jong-il regime but remain loyal out of respect for their parents or the desire to preserve their cultural heritage.
"Most Koreans in the community are not fanatical supporters of North Korea," says Professor Ryang.
Media interest, often prurient, has grown as relations have deteriorated with Pyongyang, which is closer to all-out conflict with the capitalist South than at any time since the 1953 armistice that ended the Korean War.
Japan, home to dozens of US bases, would likely be dragged into that conflict too. For conservatives, the North Korean network in Japan is a sort of Trojan horse, breeding disloyalty and even incubating spies. Nationalist politicians have blamed them for being involved in the kidnapping of its citizens. Koreans say they are being persecuted.
"I don't talk to the Japanese media because I'm sick and tired of how they portray us," says Chung Hyon Suk, a graduate of the university who now works at the Foreign Correspondents' Club of Japan. Like most students who have graduated from the university, she says there are huge misconceptions about what goes on there. "Students discuss Marx and Lenin, of course, but they can talk very freely and criticise the government. Education helped give us pride as Koreans in our culture."
With over 10,000 Koreans a year either assuming Japanese citizenship or swapping their affiliation to South Korea, according to Japan's Ministry of Internal Affairs and Communications, the minority community served by the university is shrinking, from a peak of 700,000 to just over 400,000. Many parents are sending their children to Japanese schools. For some, that's an opportunity to bury the past completely and scrap their Korean names and identities.
Not surprisingly, perhaps, one of the university's unofficial roles is to act as an ethnic matchmaking service to the declining population. "I don't hate Japan, but when you see how our community is getting smaller, it would be better to marry a Korean," says the university student Ho. "It's the only way we can be sure that our community survives."