Splinter Sex Share definition Flag When two people try to have sex while several other people are sleeping without waking anyone up. My friend and his girlfriend always try to have splinter sex when we're over....They're not to good at it. Splinter Sex by Paco the Mexican Love Slave May 26, 2005 0 0 Get merch Get the Splinter Sex mug. Buy Now — $32.95 See more merch