When a Korean taekwondo instructor visiting Singapore saw an elderly woman with no shoes, he simply gave her his own. But he didn't anticipate the storm of online interest that would follow.
Candid public transport moments often go viral in Singapore, where population pressures have made courtesy breaches a hot button issue.
But the subject of such photos and videos is usually a target of vitriol - a sullen young person pretending to sleep while a pregnant woman stands, or an irate passenger spouting random abuse.
This week, however, the country's netizens have celebrated good behaviour, in the form of 22-year-old Choi Dae Ho, a South Korean taekwondo expert on his break from teaching the Singapore National Squad.
When he saw a barefoot elderly woman board his bus, Choi knelt in front of her and gently placed his own slippers on her feet, despite her protestations.
"Ever since I was young, my grandmother took care of me. She passed away when I was 15, but I've always had a deep affection and respect for grandmothers," Choi told the Straits Times.
Unbeknownst to Choi, a fellow taekwondo squad member photographed him in the act, and posted the picture online.
It quickly went viral, and drew comparisons to the much-celebrated act of New York policeman Lawrence DePrimo, who bought boots for a barefoot homeless man last November, the Straits Times reports.
Choi, who had to run back home from the bus stop as the Singapore pavements were scorching, said he was astonished by the attention he had received.
"I did not think it was such a big deal," he told the Straits Times.
"It was a small gesture on my part, and it was something I felt I had to do, or I would regret it."