Much alike hogging, this is a judgement on the size of a splosher your no standards, man-whore flatmate has brought back home after a night out. It is simply out of ten - the greater the number the harder it is for her to fit down the corridor of your shitty student flat ie. a ten may require grease or a pole.
"Oh shit Tom's bagged a large girl. She must be an eight on the corridor scale. Fetch the butter or I'm not gonna be able to get out the front door for work."