Have you met Monique? She's the Washington area's latest pseudo-sex symbol, a mass-mail "model" for a dial-a-porn service.

"Call me anytime," beckons the passion-pink card delivered to mailboxes around the Washington area. "I'm waiting." But this calling card comes with telltale fine print: "Must be 18 yrs. of age or older." And at $6 a shot, this is no cheap thrill.

"Monique" is the latest of increasingly obtrusive dial-a-porn advertising campaigns that have targeted this area and urban centers throughout the country for the past several months. She's also the most blatant. "I love sex. Do you?" reads the card.

And to make sure the suggestive nature of the contents isn't missed, the envelopes are stamped "FOR ADULTS ONLY!!" and "You Must Be 18 Years of Age or Older to Open This!"

"Monique" (and "Linda" and "Barbi," etc.) are prerecorded party girls who use 976 phone numbers -- the toll exchange also used by such PG-rated operations as Dial a Muppet, Dial Movie Trivia and Dial Jeanne Dixon's Horoscope -- to deliver breathy and rather florid erotic fantasies.

Once confined to advertising in men's magazines and local tabloids, these telethrill companies now use bulk mailings to blanket whole communities at a time.

"They were all over Glen Burnie and Dundalk about three weeks ago . . . a total of about 500,000," said Inspector M.V. Vision of the U.S. Postal Service's Maryland regional office in Baltimore. A couple of weeks ago, thousands more envelopes, addressed to "Resident," were delivered in downtown D.C. and Georgetown, setting off a flurry of complaints to local post offices.

"The problem that we have with {Monique} is it's not inherently pornographic," said Inspector Doug Turner of the Washington field office.

"There's nothing in the postal regulations to preclude something like this," Vision said. "Whether it violates some people's moral standards or not is another question."

Postal Service officials said the only way to outfox Monique is to treat her like any other junk mail. Postal patrons can fill out a form saying they will not accept any sexually explicit materials in the mail.

"Then if they mail you stuff, it's a violation," Turner said.