ASD, or anti-slut defence is a term used in the PUA or Red Pill space. It refers to behavioural and psychological tendencies of women to resist seduction by men they really want to have sex with, in order to maintain their non-slutty reputation and self-image.
An ASD is a method used by a girl to abstain herself from responsibility during a situation where there is a likelihood of sex/intimacy.
PUA discussion of ASD centres around methods to overcome it. They discuss methods of influencing the woman’s psychological state, heightening her sexual desire, and making her feel comfortable and safe from condemnatory judgement. The aim is to prevent ASD obstructions, or manage them when they arise.