In popular culture as well as in personal stories told by many people there’s often mentions of spontaneously having sex in random places and sometimes with random people: in cars, in clubs, in bathrooms etc. But how do people do that without taking shower beforehand? Penetration is imaginable - if there’s no strong bad smell, it might be tollerable, but what about oral sex? Sounds vomit inducing.
Pheromones have a big role in sex and pairing. Sex only after shower should be a definite no-no. You should have at least half a days skin excretion on. Otherwise from your bodys perspective you might as well be fucking a silicone doll and subconscious processes for pairing are left out.