"Dear my best friend, with lots of love," moumoon's Yuka sings during their new single "BF," which does *not* stand for boy friend. Instead, it stands for "Best Friend." And, apparently, it's from the perspective of a girl who's so happy to have her best friend that she's compelled to sing about it. "Everytime, I'll be here, right beside you, because you'll always be there for me, too," goes part of the punchy and addictive chorus. And those lyrics are not translations. Most of the song is actually in English.