It's a rainy November day and young music fans are milling around the office buildings that surround Chiba's Makuhari Messe convention center. Later in the evening, they'll swarm the venue to see a performance by J-pop act JO1.

They're a patient bunch, but fans in the COVID-era need to be. The 11-member JO1 (pronounced "jay-oh-one") debuted in March 2020, right as the world was shutting down. Without stadium concerts and in-person meet-and-greets, fans had to make do with YouTube uploads and physical releases.

Tonight in Chiba marks the last date of their three-day solo debut concert “Open The Door,” originally envisioned as a nationwide tour but downsized to a trio of shows in a single venue due to COVID-19 safety protocols. It’s a full house each day, filled with fans toting official JO1 glow sticks, homemade sign boards and a lot of pent up excitement.