I often feel like I don't get Coeur de Pirate's videos. It's like the songs go one direction and the videos another...and then an abrupt ending. Take, as a case in point, Ensemble. You get the great instrumentation, the little-girl voice, the lovely Beatrice Martin, and overall a wonderful tune. And then you watch the video and you wonder, "Have I gotten this whole song wrong?"
So you check the lyrics, just to make sure. You were right: the song has nothing to do with an evil twin or high school. One presumes the man in the song is the yo-yo dribbling guy making out with some woman but what about him? And then it's over.
Do yourself a favor: watch the video once, just to see what it's like, and then listen to Ensemble without it. Coeur de Pirate has a gift for making perky songs about painful topics, of which this is a great example. Let me know if you think the video fits better that I do.