Guess? Alright I'll give it a try.
It's the industrial revolution and many people are drawn to the cities by the promise of wealth and jobs, especially in the growing matchmaking industry. Unfortunately the poor working conditions and sanitation problems in London at the time aid in the spread of disease and a plague like epidemic sweeps through the city. (Perhaps the disease is similar to Phossy Jaw?)
The main character, the son of a poor matchmaker (the boy in the video), witnesses the decline of the city and it really hits home when his parents are infected. Now he must travel across an industrialized (steampunk perhaps?) England with only his close friend (the girl) to help him in his search for a cure for his sick family and, by extension, the rest of the city. It's a race against time before his parents, his city, and perhaps his entire nation succumbs to the disease.
Anyway, the art is nice, I like the water-color like colors and the characters all look unique and expressive. The animation is nice and smooth. The entire thing works together very nicely. The only thing that annoyed me was the constantly shifting outlines of the characters. But I understand that this is just a concept animation more than anything.