Gussie Two-Grins

A bottle-covey and no friend of the City Watch. Called "two-grins" because during a pub fight he was once hit square-on with a broken glass that gave him a permanent grin. As he was so fired up on adrenaline and alcohol, this did not register with him at the time.

At the age of about twenty-one, Samuel Vimes runs into him, and it is a real education, since he is the dirtiest fighter he will ever meet. He sees the weapon in anything...

Annotation

Giving somebody a "permanent smile" (also known as a "Glasgow Smile" and a "Chelsea Smile") by hacking the corners of their mouth upwards across their cheeks was a favourite torture applied by psychotic gang-leader Reggie Kray with a cut-thoat razor. In urban mythology, the attacker makes a small cut either side of the mouth then kicks the victim inna fork causing him to scream and disfigure himself as the skin rips all the way up. Heath Ledger's Joker in Christopher Nolan's The Dark Knight seems to have been a victim of this at some stage.