FWIW Loona are a "they" not a "she". They're a big (12 member?) girl group but haven't officially debuted yet as a whole group. For the last couple years they've been putting out teaser singles like that one where each member gets a solo song and some songs in groups of 3 etc.After looking into Loona a bit it seems she puts a lot of same sex couples (seems mainly women) in her MV's.
I only recently found her myself haha. The song has kind of an 80s 90s vibe that I really liked. It has a more unique sound than some of the other mainstream stuff. Too early for me to tell if all her stuff is like that or not but that song is fire imo.
I know a lot of people (especially international fans) are getting really hyped about them