Bittersour

While spending a happy night with a man he brought home for a one night stand, Jiwon hears loud fighting coming from the apartment next door. He brushes it off at first, but starting the very next day, drunken breakup songs echo through the night nonstop. Unable to take it anymore, Jiwon finally goes over to confront the neighbor.

There, he finds Hyun watching a video from a singing competition that has become Jiwon's ultimate embarrassing black history. And when the man from the video suddenly shows up in person, Hyun is just as shocked...

(Source: Lezhin Entertainment, translated)