A little like 'face only a mother could love', but worse. Someone whose appearance instantly provokes immediate thoughts of very violent acts. You'd probably be doing them a favour, in fact.
as per "that (insert name here)'s got a face only a fist could love"

Examples:
Sonia off Eastenders
Any Liverpool fan
The sort of bloke who walks around town without a shirt on. (classless scum)
by Androsbeardinho June 7, 2007
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