Just watch the video intently. I think it's pretty much open to interpretation and I haven't really been able to figure anything solid out. As far as I can tell, the main thing is that this creepy Miku and her friends are creating machines to look like humans, which then act out in vain. Then one falls off the assembly line and nobody knows what to do, nor do they care. You can make your own ideas about the story though, and what it means.