She wouldn't leave without a kiss. So Kimberly, a blonde college-age student with an evah so slight Southern drawl, leaned over the counter of the Tasty Diner in Harvard Square and kissed Karl Stevens, the late night grill cook, smack on the lips. The exchange was great entertainment for tasty patrons at 2:30 a.m. one recent Thursday night, what Karl calls the bar crowd. And the standing room only crowd cheered.

Karl played to the audience. First he gave Kimberly a lollipop, more cheers, then he autographed a Tasty postcard, as "Tasty Karl."

"Karl, I'm sooo touched," said Kimberly, sounding just a little bit like Scarlett O'Hara. But this was no Southern belle, for after slipping the postcard down her blouse, she politely demanded Karl's phone number. He refused.

"That is one of the stupidest girls I have met in my life," Karl said after she left. Karl should know. As late night grillcook at the Tasty, Karl has met his share of off-beat customers, working the graveyard shift three nights a week. "She just wanted me because she thought I was from the other side of the tracks," he says.

Actually Karl, who sports a small hoop earing and a scruffy reddish-brown beard, is a 21-year old guitar student at the Berklee School of Music. He says he gets a kick out of playing up to late night visitors who expect bizarre behavior from a diner cook. "Sometimes I practice my expressions before a mirror," he jokes.

Karl also monitors and censors the various types of entertainment that play in the Square's smallest theater. When a bunch of drunken men wearing Harvard football jackets begin insulting women and cursing, Karl responds. "Cut it out, this is a PG joint," he yells above the din of "Pink Cadillac" by Aretha Franklin.

This element of entertainment is not out of place in the Tasty late at night where reality and fantasy mesh together in a surreal atmosphere that pervades the cramped, flourescently-lit quarters of the 70-year old coffee shop overlooking Cambridge's commercial hub.

I could philosophize about the Tasty, the ebb and flow of different types of people all caught up in the constant motion of time. I could wax eloquently about how the clamor of people crowded into this vintage 1950s diner mimicked the musical rhythms of "Classic Hits" WZLX.

I thought of doing all these things while serving coffee to customers and washing their dirty dishes. This night in the Tasty was my chance to a prophet for the next generation. Karl had given me an apron at midnight, he had agreed a couple of days earlier to let me work the night shift with him, and by 3 a.m. I not only thought I was a expert at my job as coffee master but that I was a genuine character as will.

But at 7:30 a.m. on Friday morning, my shift over, I met for the first time Dr. Zeke. The good doctor, and I am not quite sure what his speciality was, wore a black velvet jacket and a rose in his lapel. His hair had been permed and he spoke in a thick Black dialect. A little on the hyperactive side, the Doctor tried desperately to convince Karl to give him some free food.

After telling us that he was "so po" that he had been born in the back of a taxi, Karl retorted he was "so po"' that he had been born on a hubcap in the middle of the road. Dr. Zeke fell off his chair and ran out of the Tasty into the middle of the street.

Eventually, The Doctor returned to his stool to begin eating his food while I left with Karl. It was then that I realized two things. The first is that to philosophize would be a mistake because the different people in the Tasty are much more interesting than I am; and second that a coffee regular has cream and sugar, (not just cream, which is the way I drink it.) In those two ways my perspective on life had been widened.

But that doesn't mean Karl Stevens doesn't philosophize. "I'm thinking about writing a book about this place," says Karl, "I would call it, 'I could help them if I would.''' Karl's title refers to the huddled masses of homeless and unemployed who are the regular denizens of this eating establishment late at night.

These stalwarts are as diverse as they are different from the college students who swarm around the counter from 12 to 3 a.m. and the laborers who casually sip coffee on swivel stools.

The first of the late-night stalwarts that I met was an elderly women, looked about 60, whose L.L. Bean-like clothes belied how haggard she looked. When I first saw her I thought she seemed someone who might start asking me about where I went to school and how old I was and other such pleasantries.

But she wasn't in the mood to talk. She ordered a coffee regular, glared at me until I brought it and then asked for the music to be turned down. I relayed the message to Karl, but he refused. I relayed his response, and she threatened to report him to a superior. Karl said let her. I gave her this message, she looked me over carefully, said, "I am sick and tired of him."

"Let her go, she's a manic depressive insomniac who was in love with the guy who worked these hours before me," Karl said and he quickly turned back to he work at the grill. Just then the song "I've Got the Music in Me" blasted from the radio and Karl began to pound greasy hamburger patties on the skillet with the rhythm. "I love this song," he shouted.

Karl loves a lot of songs, and music dominates the atmosphere of Tasty late at night. The rhythm sets the working pace and the decibel level controls the frenzy of the crowd. Karl, being a student of music, admits to changing noise levels in order to adjust the crowd. He likes' em frenzied.

One person who doesn't hear the music is Bill. He wears a walkman and indicates what kind of service he wants by hand signals. Twirling his finger in the air indicates that he desires a cup of coffee. It took me a while to figure this out, but eventually I got it to him. In reponse, he congratulated me with a thumbs up.

Bill, a tall, lanky man, then casually sat in his corner and watched the students invade his hangout and eventually leave. He smiled at the students, made eye contact with me when he wanted more, and soon introduced himself, uttering the only words I heard him speak, "How you doin?"

Some of the regulars are a little younger than Bill and the elderly women. One such person is Santos, who I saw in the Square many times before actually meeting him at the Tasty. He sports several earrings and a real smooth mannerism that goes with his jean jacket. This guy also was mean, looking to start a fight with a redhaired guy who sat alone at the table. But Karl refereed and brought the conflict to an end.

To these regulars, Karl calls them the "real people" who dominate his place after 3 a.m. when the bar crowd leaves and it becomes a social club where everybody knows each other, I was the "celebrity grill cook." That was pretty good in my mind because at least I was sort of real. But the two Pine Manor students fresh from the Picadilly Philly instantly recognized me as the Harvard student I was.

When Harvard students visit the Tasty pack into the cramped diner, they behave as though they were standing around in Weld Hall and a freshman party. There's constant noise, fights break out and couples make out. These are not model customers; they aren't real people. In fact Karl has to make some of them pay ahead of time because he knows they'll run out on him after they have eaten their food.

But students like bantering with Karl. Karl flirts with the women.

In the morning Karl stops the witty back-and-forths and begins serious conversation with the customers, most of them middle-aged laborers, men who eat their eggs breakfast in the Tasty. During this time the diner goes through eight gallons of coffee and a dozen eggs.

The stories they tell have the ring of male bull session. One man wearing blue work clothes tells how he tried to pick up a beautiful woman at a bar. "I went up to her and I said, 'Honey, name your price, I'll do anything but I have got to be with,'" he recounted. "So she turns to me and says, 'I go with women." Well that just floored me, I go with women, I couldn't believe it," he told the assembled coffee drinkers. "She just said, 'I go with women,' right there in that bar, and she was so beautiful." He proceeded to repeat the story, two more times.

Karl probably has heard the tale several times before because in the Tasty, which holds to the motto "Round the clock conviviality with mustard, onions and relish," most things are constant and there is always a sense of circular return. Indeed just after most of the men left for their jobs some of the Harvard football players who had been there the previous night sat down at the counter in ties and blazers. They were having breakfast before they left for a road game and this time, in the sedate atmosphere of early morning, Karl didn't make them pay in advance.