Fans think that Red Velvet's "Red Flavor" could possibly add to the vampire theory.
The theory that Red Velvet had been vampires since "Ice Cream Cake" is pretty popular in the fandom, and "Peek-A-Boo" adds more fun to the theory. However, fans are now looking back at "Red Flavor" and it actually fits the vampire theme perfectly.. if the 'red' they're talking about is actually blood. The entire song fits pretty well, especially lines such as "I'm curious about your red flavor", "You're so nervous you start sweating," "I'm gonna have you and do whatever I want", and more.
Of course, it's all just for fun but many fans think it actually fits really well, and that it turns a super cute song originally thought to be about summer fruits (like watermelon) to be a pretty scary song.
What do you think about the interpretation?