K-pop idols Baekhyun of boy band EXO and Soyou of girl group SISTER recently collaborated on a love song that is making their fans go wild since the video was uploaded on youtube on the eve of Valentine's Day. The video for the song "Rain" earned over one million views in less than 24 hours and is now on its way to two million views in less than a week. But more than that, it managed an all-kill in all eight Korean music charts in the first nine hours.

According to a report by Billboard, the duet likens the feeling of a relationship's end to the atmosphere when it rains, which was perfect to bring on the feels for Valentine's Day and even beyond. The article credited the strength of Baekhyun and Soyou's vocals as well as the perfect blending of melodies for the chorus.

Based on early reviews, the collaboration between the two Kpop superstars seemed surprising at first but they brought out a more mature sound from each other. The reviews credited the blend of Soyou's raspy voice with that of Baekhyun's powerful voice to produce a wonderful song and a definite chart topper.

The video immediately reached one million views from supportive fans of the two artists and earned high praise from the viewers on the comments section. Some of the commenters expressed that Baekhyun and Soyou should perform "Rain" live with a rainy background in one of the concerts of either EXO or SISTAR.

As of February 17, the music video for "Rain" has garnered 1,767, 419 views keeping it on track to reach two million in a week. The video has also earned 119,179 likes on youtube.

A report from Soompi also indicated that the song achieved the #1 spot on all of eight Korean music charts for an all-kill. And this was achieved in a matter of nine hours, an amazing feat for any new song release.

This was not the first time Baekhyun has collaborated with other artists outside of his boy band EXO. He did a duet last year with Miss A's Suzy Bae for the song "Dream."

Soyou, for her part, also collaborated with Junggio and rapper Lil Boi for the 2014 hit "Some." Both songs performed well on the local and international charts.