Directed by frontman Kier Griffiths, the video follows a suburban misfit trying to find her place - with a decidely goulish twist.
Fist City have also announced that they'll be joining Girl Band at a number of their upcoming European dates.
New album Everything Is A Mess is released 22 June via Transgressive Records.
Watch the video for "Hey Little Sister" below, and find Fist City's upcoming dates with Girl Band beneath.
October
20 - Brussels, Belgium, Autumn Falls Festival
21 - Kortrijk, Belgium, De Kreun
22 - Utrecht, Netherlands, ACU
23 - Rotterdam, Netherlands, V11
24 - Zwolle, Netherlands, Let's Get Lost Festival
24 - Groningen, Netherlands, Vera