So this isn't exactly a mashup (which is why I stuck it here), but it's simultaneously eerie and amusing how well Nu'est's dance and Sage The Gemini's song go together. This is a link to my personal Google Drive because I don't want to violate any (no matter how loosely) Copyright laws...which would be counterproductive to supporting the artists. Make sure you let the video load all the way before you play it; Drive isn't the best video player but having no lag is crucial to the vid.
Also: EXPLICIT LYRICS WARNING. I SAY AGAIN: EXPLICIT LYRICS WARNING. Don't click it if swearing offends you. (I didn't have a clean version of the song lol)