If you make a public announcement, then you start losing male fans and draw attention for people to publicize and scrutinize your private relationships. So to keep it on the DL but still get the word out, their manager helped them find ways to drop hints that fellow idols are used to spotting by putting them right in the choreography of their new song.
Sojin decided to take a kpop classic and add an extra gesture to make it clear.
|Now open for business. Come hither.|
Props to their manager for letting them live a little rather than throw away their youth being slaves to archaic and cruel rules for no reason but to indulge the delusional fantasies of misogynistic males who want women to be sexy yet count them actually having sex (unless it's with them) as an impurity. Perhaps the decision was made because their manager is a woman (damn, she looks like Sohee/Sohyun) but either way, it's good to see they are free and were able to get the message out before MOGEF censors the fuck out (literally) of their choreo.
Thanks again to fiddle.se for the gifs.