"When the concert was cancelled, I was really upset," said one disappointed fan, Im Yu-mi, 19, sitting in her room on a chair covered by a BTS blanket.
Im scoffed at the idea that the concert cancellation had cooled the fervour of BTS' global fan base known as ARMY, an acronym for Adorable Representative MC for Youth.
"It's nonsense," she said, waving a glowstick and tapping her foot to the band's latest music video.
Around 200,000 fans had been expected to go to the concert, which was to be the first leg of BTS' "Map of the Soul" tour of 18 cities, including Los Angeles, Washington D.C., London and Tokyo.
Those concerts have not yet been cancelled, but the swift spread of the virus globally has cast doubt on the rest of the tour.
On Tuesday, BTS announced that ticket sales for the European leg would be delayed by several days because of uncertainty over the coronavirus. Their next concert in Santa Clara, California, on April 25 remains unchanged, according to their music label, Big Hit Entertainment.
BTS, a seven-member boy band, has spearheaded a wave of Korean pop music far beyond Asia since their 2013 debut.
Earlier this month, the band's new album "Map of the Soul: 7" topped the Billboard 200 album chart, following three other similar successes.
Plans for a large media event in February for the album launch were ditched due to the coronavirus health scare. Instead the band live-streamed a news conference.
South Korea has reported over 8,400 confirmed cases of coronavirus, with 84 deaths.
Last week, BTS fans wearing face masks gathered to celebrate the birthday of band member SUGA at a cafe decorated with posters of him. They had their temperatures checked and were given hand sanitiser at the door.
SUGA is originally from Daegu, the city hardest-hit in the country's coronavirus outbreak, and has donated 100 million won ($80,600) to prevent its spread, according to Hope Bridge Korea Disaster Relief Association.
About 11,000 BTS fans followed suit, the association said, donating more than half a billion won. Many of them have even given their ticket refunds from the April concert to purchase relief goods for the needy.
