Maskarade are a French duo. They love Frank Sinatra, Bob Marley, and MashUps. They appear to enjoy the process of making their little Pop creations as much as anything. And you get a bit of the feeling of their creation enjoyment when you watch the videos. They also seem to be primarily YouTube artists at this point (worked for Beiber).
Did they do another Christmas song for 2016? Why, yes, thank you for asking. Also free to download via Soundcloud is "White Christmas" (yeah, you want this one, the least you can do is pay them a visit), which is pretty much straight a cappella doo wop (in the tried and true Ravens arrangement).