Actually: You sure can — and many do.

Oral sex is rather popular, as these things go: According to a national survey, about two-thirds of young adults, ages 15 to 24, have engaged in it, a rate that remains consistently high.

But perhaps because sex in general — and oral sex in particular — is vested with personal preference and meaning, 27 percent of women and 24 percent of men do not have their first experience with fellatio or cunnilingus until after having had vaginal intercourse, according to the National Center for Health Statistics.

And most people — around 71 percent — consider oral sex (“O.G.,” in research-speak, for “oral-genital”) to be “sex,” according to the Kinsey Institute at Indiana University.