The group NiziU is making headlines after revealing a dizzying injury episode experienced on a large festival stage.

Recently, a behind-the-scenes video of "COUNTDOWN JAPAN 25/26," held at the end of last year, was posted on NiziU's official YouTube channel.

The released video captures the excitement of the members preparing for the festival stage, their final schedule of 2025, as well as the real scenes backstage. In particular, an injury episode revealed by a member after successfully completing all performances had fans holding their breath.

Rima explained the situation at the time, saying, "After the first song ended, the microphone hit (my finger) with a 'bang'." She continued, "I thought it was just a cut, but I didn't know it was bleeding," adding, "I wiped it off in a hurry," which came as a shock.

The injury didn't end there. During the intense performance, her fingernail even flew off. Rima added, "In the midst of that, my fingernail flew off too," giving a glimpse into the intensity of the stage.

However, what was surprising was the sensation Rima felt at the time. She displayed extraordinary professionalism that made her forget even the injury, stating, "But (during the performance), it didn't hurt at all, so I was fine," and added, "I poured out all the passion of the year, sweating as if I had taken a shower."

Meanwhile, on this day, NiziU brilliantly decorated the end of 2025 by unveiling the stage for their new song "Happy Day" for the first time, receiving enthusiastic cheers from the audience.