Bespectacled and with toothy smiles, students Jolly Lam, 21, Clare Wong, 20, and Phoenix Ng, 21, quiver like a trio of shy rabbits.
In a low whisper, Ms Lam - a Chinese Studies undergraduate who wants to be a teacher - confides that she never, ever, skips classes. Except for last week.
What comes next is even more shocking. "I am willing to be arrested and jailed for any civil disobedience action if the government tries to introduce Article 23 again," she says, referring to a national security law shelved in 2003 after a protest march by half a million Hong Kongers. It would require the city to prohibit acts of "treason, secession, sedition, or subversion", and could, say, ban any group banned in mainland China.
Ms Lam and her friends were taking part in a week-long boycott of classes to protest against what activists denounce as "sham democracy". Last month, Beijing announced strict rules for the 2017 chief executive race, essentially restricting the contest to candidates it approves of.
On a Wednesday morning, hundreds of university students were sprawled out over the lush green of the Tamar Park next to the government headquarters in Admiralty. The air was almost carnival-like but for a lecture by Chinese University of Hong Kong (CUHK) academic Edward Yiu on the link between cronyism and the city's housing woes.
Things however turned ugly on Friday night when over 100 students broke into the government compound, while thousands remained outside. Scuffles broke out between the police and protesters, with pepper spray and warnings failing to disperse the students. At least six have been arrested, including the leader of the Scholarism activist group Joshua Wong.
Hong Kong Federation of Students (HKFS) secretary-general Alex Chow, 24, reportedly admitted that the action was pre-planned.
In Hong Kong's ongoing and deeply polarising battle for constitutional reform, students filled with youthful idealism and righteous rage have been at the forefront, often even moving ahead of older, more cautious activists.
On July 1, for instance, they went ahead with a mini-Occupy Central exercise in Chater Road despite the Occupy organisers' preference to wait until they had heard the decision from Beijing. More than 500 were arrested for illegal assembly, and obstructing the police.
The youth are Hong Kong's post-1990s generation, aged 24 and below, who grew up after the 1997 handover from British colonial rule to China. Their push for a bigger say in the city's affairs is often channelled through associations such as the HKFS - comprising university union members - and Scholarism, led by secondary school students.
Student activism is not new to Hong Kong.
In 1971, HKFS members were arrested for illegal demonstrations over the disputed Diaoyu Islands. Two years later, students staged an illegal sit-in to criticise the British government for its failure to tackle rampant corruption.
Students were also involved in advocating for the rights of the Yau Ma Tei boat people, who were living in overcrowded conditions. Among them was Professor Lui Tai Lok, now a Hong Kong University (HKU) sociologist, who recalls being arrested on a bus for illegal assembly en route to a protest at Government House.
In 2010, the post-1980s label came into vogue when young activists protested against the building of a high-speed railway linking Hong Kong to the mainland.
Now, an even younger, more politicised and angrier wave has appeared at the fore.
While protests in Hong Kong remain largely peaceful, confrontations have become more commonplace. In June, a melee broke out when protesters tried storming the Legislative Council building over New Territories town plans.
Prof Lui, who has written a book on Hong Kong's previous four generations, muses: "Nowadays, there are more angry young people who want to do something, and who are engaging in a lot of expressive actions."
Much of this stems from deep disenchantment with what Mr Chow terms a "twisted" political system that represents the interests of Beijing and businesses rather than those of the people.
In an earlier interview with Think, Mr Chow, a student of comparative literature and sociology at HKU, believes "street politics is more effective; it can generate pressure on the government".
He adds: "Violence can be justified at times."
Such sentiments are borne out by a study last year by the Ideas Centre, a research centre in the city, which polled more than 1,000 post-90ers and found that compared with their predecessors, they had greater distrust of authority, including the government and mainstream political parties.
Many respondents believed that protests, rallies and hunger strikes could empower people and bring about change, and that behaviour such as hurling objects or cursing at establishment figures, could help draw the public's attention. More than three-quarters of those polled said they believed disputes and conflicts were inevitable but they were optimistic that "if we fight back, it is possible to effect change".
Such thinking is condemned as radical, naive or political posturing by some older Hong Kongers.
But what drives the young?
Ironically, almost two decades after the handover and despite growing links, younger Hong Kongers are more estranged than ever from China. For post-90ers, what is at stake is the struggle for a collective local identity.
"I am a Hong Konger, not a Chinese," says CUHK science student Sasiphat Fung, 21, firmly. Citing issues such as human organ trafficking, she adds: "It embarrasses me to be a Chinese as many horrible things have happened in China."
A big part of the aspiration for a Hong Kong identity is the desire to be masters of their own destiny - not necessarily independence but to be able to choose their own leaders who "guard our interests, not Beijing's".
HKU sociologist Paul Yip says most students believe they occupy the moral high ground.
Influenced by Western liberal democratic ideas, their thoughts on issues such as political systems are refracted through such lenses because "they haven't seen a better model apart from the Western one", says Professor Yip. A Communist China that imprisons Nobel laureates like Liu Xiaobo inspires little admiration in them, he adds.
Meanwhile, British colonial rule is often viewed through rose-tinted glasses. HKU English studies student Rachel Ma, 18, puts it thus: "The British introduced democracy to Hong Kong before China took it away."
Prof Lui says drily: "There are very imaginative ideas of some kind of benign colonialism in Hong Kong where democracy flowered."
The sociologists blame inadequately nuanced teaching of history in schools. While the government has sought to include more Chinese history in the curriculum, some have noted that the "idealised" versions - grand narratives of modern China's rise - have backfired and drawn derision. On the other hand, Hong Kong's own colonial history is dealt with in broad strokes.
Meanwhile, the Internet provides inspiration with its snapshots of overseas student movements. Facebook and WhatsApp are influential tools for information dissemination, and for youth to organise themselves.
Ultimately though, those willing to go all the way in civil disobedience remain in the minority. Even as thousands of students skipped classes last week, many more stayed in school.
Some also question the effectiveness of the youth's actions. "There is a lot of passion but most are not actions aiming at some tangible result," said Prof Lui. "There are no proposals of reform or future directions."
Eventually, the students will go home, though for some, the "fight for democracy" is likely to go on.
Their critics might hope that as they grow up, they will channel their energies into more pragmatic concerns like landing jobs and raising families. But even in this, post-1997 Hong Kong administrations - under which inequality grew, home prices rose and job opportunities shrank - have done little to foster confidence in the future among post-90ers.
Issues of identity will also not be so easily resolved and, as the past 17 years have shown, time is not necessarily on the establishment's side.
This means that even when the current strife passes, Hong Kong's kernel of unhappiness will continue to fester.
Additional reporting by Pearl Liu