Our closest primate relatives are the Chimpanzees and Bonobos. Which do you think we most closely resemble re: our behavior? Or maybe humans are split--Hobbyests and Prudes lol
The following was copied from an online description (not mine).

"The major distinctions between bonobos and chimps are behavioral, and the most conspicuous do involve sex. Both in captivity and in the wild, bonobos practice a remarkable diversity of sexual interactions. According to de Waal: “Whereas the chimpanzee shows little variation in the sexual act, bonobos behave as if they have read the Kama Sutra, performing every position and variation one can imagine.” For instance, they mate in the missionary position, something virtually unknown among chimpanzees. But their sexiness isn’t just about mating. Most of those variations are sociosexual, meaning that they don’t entail copulation between an adult male and an adult female during her fertile period. The range of partners includes adults of the same sex, an adult with a juvenile of either sex, and two juveniles together. The range of activities includes mouth-to-mouth kissing, oral sex, genital caressing by hand, penis-fencing by two males, male-on-male mounting, and genito-genital rubbing (G-G rubbing is the shorthand term) by two estrous females, who moosh their swollen vulvas back and forth against each other in a spate of feverish sisterly cordiality. Usually there’s no orgasm culminating these activities. Their social purpose seems to be communication of various sorts: expression of goodwill, calming of excitement, greeting, tension relief, bonding, solicitation of food sharing, and reconciliation. To that list of benefits we might also add sheer pleasure and (for the juveniles) instructional play. Varied and frequent and often nonchalant, sex is a widely applied social lubricant that helps keep bonobo politics amiable. De Waal again: “The chimpanzee resolves sexual issues with power; the bonobo resolves power issues with sex.”