Prosecutors ended their case against reputed Washington massage parlor "kingpin" Louis Michael Parrish yesterday afternoon after a day of graphic testimony about what one witness called Parrish's "business of sex."

Parrish, 34, a pudgy, baby-faced businessman described as "The Old Man" in court testimony, did not offer any rebuttal evidence to the government's charge that he ran what the FBI has described as the area's largest and most sophisticated prostitution ring.

The government rested its case against Parish and two associates after dropping several counts of a 13-count racketeering indictment against them. Neither Parrish nor his associates, Larry J. Wadino, 31, and Kathy Lynn Caldwell, 25, offered any witnesses in their defense in the case, which probably will go to a jury of 10 men and two women today.

The government agreed to drop four counts of aiding and abetting prostitution against Wadino, who was portrayed in court as Parrish's bookkeeper and business manager. Two counts of prostitution against Parrish were dropped as was one count of prostitution against Caldwell, described in court as the manager of one of Parrish's call-girl services.

At one point, while the jury was out of the courtroom, defense attorneys Jacob Stein, John Down and Richard Cooper said that while it was obvious that prostitution was taking place at the Parrish parlors, their clients never told anyone directly to commit the act.

U.S. District Judge Oren R. Lewis disagreed and denied defense motions to strike the conspiracy charge against the three. "I think there's plenty of evidence to show a conspiracy, if the jury will believe it," the judge said.

Parrish's "sex business" was described in detail by former masseuses and massage parlor managers who portrayed Parrish as a reclusive businessman who disguised himself behind ficticious names and various corporations'

Bank accounts to receive monies from the massage business were established in phony names, according to testimony from one Alexandria bank official. Assistant U.S. Attorney Henry E. Hudson told the court this was part of Parrish's overall "scheme."

In other testimony in federal court in Alexandria, former masseuse Dianne E. Jones described how Parrish wanted to establish a sado-masochistic facility at one of his massage parlos in the Northern Virginia city.

Jones told the court she was an expert in the "English massage," a service which included "domination and/or humiliation" of the client. She said she purchased sexual paraphernalia at Parrish's request for the Alexandria facility. The devices, which included black leather whips and harnesses, were introduced as evidence'

Phillip Paul Bates, who said he was hired by Parrish to distribute leaflets advertising the various massage parlors and outcall services, described the "English room" as "brick walls, with racks, stretchers... different English equipment."

Bates also described the procedures the employes were advised to follow if arrested. "Give our name and social security number and we'd be out of jail before we were booked," he told the court.