A preloaded song on an old MP4 player

This could be a long shot 😅

Around 2008-2010ish I had an MP4 player that came with a preloaded song & music video. I think it was Japanese but could’ve maybe been Chinese or Korean.

The memory of it is very vague but I think in the music video it was set in a school & there were multiple singers dressed as school kids.

I thiiink it started with a girl with a black bob & the different singers came after. But that’s about all I can remember.

Any ideas?