Even casual sex has a large component of intimacy and affection.
There's a surprising amount of intimacy (foreplay, eye gazing, & cuddling) when people have 'casual sex' -- especially if they really like 'casual sex'. (N = 639 young U.S. adults). HT
#SexScienceNews: Casual sex isn't just about sex! Among undergrads 53% men & 62% women enjoy cuddling, 38-46% would stay the night, & 27% are up for eye gazing! Such desires are even stronger for those who prefer hookups to romance.
who doesn't engage in foreplay? mainly people who hook-up but prefer long-term mating. those who hook-up but prefer hook-ups do engage in foreplay (and cuddling, eye-gazing, etc.).