This is uber-cute and worth repeated viewings -- but there's a bit of an underlying story, to my mind. Marcel the Shell is voiced by SNL cast member Jenny Slate, and if you've been watching SNL on and off the past few years and can't seem to recall who Jenny Slate is, you're probably not alone. It's tough to stand out on SNL, especially for freshman cast members, and especially, I think, for lady freshman cast members -- just ask my pal (well, she was in a thing I did once) Michaela Watkins, who was on SNL two seasons ago and did a few genius bits but was mostly underused and the unceremoniously dumped after just one season.
Jenny Slate seems to be faring somewhat better, though after two seasons on the air she's still primarily known for dropping the f-bomb on live TV. Hopefully the impending virality of this video will convince some SNL higher-ups to give her more face time.