Click on the image above to see the music video on youtube
Apparently the music video tells us about the off-on relationships of Taylor and Harry Styles as hinted from the lyrics itself.
Taylor colaborated with a fashion model named Dominic Sherwood, whom he had a heterochromia iridum condition, which his eyes colors are different, one eye colored brown, and the other perfectly blue.
See his complete bio on wikipedia here :http://en.m.wikipedia.org/wiki/Dominic_Sherwood