The MV was inspired in the terror movie called "Midsommar", which shares the same story line. The girls take this visitor to a ritual, you can see that he is trying to run away from them. And just like you pointed, Red Velvet is a girl group remarkably known for its dark and mysterious image and vibe. And at the end, in my pov, they are celebrating their femininity, nature, celestial love for each other, cosmos and beauty. Thanks for sharing this amazing reaction