Kassy has revealed an emotional music video teaser for "Tock Tock".

In the MV teaser, Kassy performs the beautiful ballad on a cloudy day by the Han River. "Tock Tock" is about enduring heartbreak and compares teardrops to the rain, and it's set to release on July 2 KST.

Watch Kassy's "Tock Tock" MV teaser above, and let us know what you think in the comments below.