Susie is the deuteragonist of Do's & Don'ts. She was first introduced in Hiding a Body, but her name was not revealed until Mate Selection.

She is a fat girl who loves to eat, which was first demonstrated in Mate Selection. In Mate Selection, she appears to have a crush on Jimmy. Also, in Deserted Island, when Jimmy and Susie are in front of a waterfall, she quotes it to be "romantic". She owns a dog called Munchkin, but Jimmy kills it in Ritualistic Sacrifice.

She has been killed twice in the series: Jimmy smashed a shovel on her skull in Hiding a Body to respect the third law of body disposal (no witnesses), and Jimmy backstabbed her in Deserted Island after she tried to escape him but failed because she was unable to run for too long.