existentialist sex Share definition Flag A sexual experience that is planned in advance and set up to be different or weird on purpose. She was bored enough to take up his suggestion for existentialist sex and wore the moon boots and feather boa. existentialist sex by quazy_quisp April 11, 2009 0 0 Get merch Get the existentialist sex mug. Buy Now — $32.95 See more merch
