The kisses of slave girls on Gor

There is a difference between the kiss of the free woman and the kiss of the slave girl; the slave girl yields to her master; the difference is unmistakable. It is said that he whose lips have never touched those of a slave girl does not know, truly, what it is to hold a woman in his arms.
Beasts

Although we are not told what the "eleven kisses" are, (names of the kisses) or how these particular kisses are performed, we are given the understanding that the "eleven kisses" are so basic that it is preposterous that a "trained pleasure slave" could not know them. (Perhaps similar to claiming one is a Chief Financial Officer on earth, yet not knowing how to add or subtract?)
“Another loot girl taken by our noble Captain, Bejar, in his brilliant capture of the Blossoms of Telnus,” called the auctioneer. He was also the slaver, Vart, once Publius Quintus of Ar, banished from that city, and nearly impaled, for falsifying slave data. He had advertised a girl as a trained pleasure slave who, as it turned out, did not even know the eleven kisses.
Explorers

The "eleven kisses" appear to be the basic kisses that slave girls learn. We are given enough information in the books to understand that there are more than eleven kisses on Gor and that trained pleasure slaves (those select few trained for months in slaver houses to be specifically "pleasure slaves") are taught a large variety of kisses uncommon to most slaves.

Here, a mention of "the hundred kisses" (which would reasonably be assumed to be beyond the basic eleven kisses).
"They cannot even speak Gorean," said the man beside me.
"Barbarians," I said.
"Yes," he said. The girl had spoken in English. This had confirmed my surmise as to their origin. I had come to Seibar's market out of curiosity. I had heard he was the major dealer in Kailiauk for barbarian slaves. I did not know, but I suspected that he himself was not in league with Kurii, but merely purchased wholesale lots of such girls from one or more of their agents. Such girls, I gathered, from my conversations with the teamster with whom I had ridden to Fort Haskins, were sold at various points along the perimeter. I had, earlier in the afternoon, on one of my purchased kaiila, scouted the terrain north and south of Kailiauk. In my ride I had come to one place, sheltered among small hills, in which I had found scorched grass and several, rounded six-inch-deep impressions in the earth. It had been there, I speculated, that one of the steel ships of the Kurii had landed. Also there were wagon tracks leading away from the area, toward Kailiauk. I was less fortunate, at various small camps and outlying farms, in obtaining information as to the possible whereabouts of a white trader named Grunt. I did not approach the Ihanke, nor did I wish to do so, if possible, until I knew exactly what I was doing. I did not know, for example, even if it were guarded or not.
"Even if such girls understood Gorean," said the fellow next to me, amused, "they could probably not even understand what was required of them. They probably do not even know the hundred kisses."
"They could be taught," I said.
"That is so," he laughed.
Savages

This quote refers to special training a slave is receiving in a Slaver House. (Three girls out of the 4,000 - 6,000 slaves in the House at the time are chosen to be trained by the best trainer in the house - training that takes months.)

Elizabeth, one of the three, is taught "an unbelievable variety of kisses". Given the way the quote is written, "a large number of dances, dozens of songs, and an unbelievable variety of kisses and caresses", it is impossible to tell how many kisses are taught, but it appears that it would be more than "a large number" (the dances) or "dozens" (the songs). Certainly we can accept that "an unbelievable variety" refers to more than "eleven" (as in, the eleven kisses)

Elizabeth was, however, to my satisfaction, taught a large number of things which, to my mind, were more appropriate to the training of slave girls, including a large number of dances, dozens of songs, and an unbelievable variety of kisses and caresses. The sheer mechanics of her repertoire, theoretically outfitting her to give exquisite pleasure to anyone from an Ubar to a peasant, are much too complex and lengthy to recount here.
Assassins

We see that toward the end of the intensive training, the girls return to various "basics", and "basic kisses" are mentioned among them.
I sensed that our training was coming to an end. We were returning to various basics, almost as elementary as scales to the musician, such things as basic kisses, caresses, position, attitudes and movements.
Kajira

This kiss is not described, but simply named as a specific "kiss". This kiss is part of the intensive training being given to the three slave girls referred to above. Whether it is one of the more basic kisses, or among the more advanced kisses taught in intensive pleasure slave training, we do not know.
"And yesterday," laughed Elizabeth, rocking back, clapping her hands, "when Sura asked him to stand forth that one of us might approach him to administer the First Kiss of the Captive Slave Girl, it was you who first sprang to your feet."
Assassins

A specific kiss that a slave girl invented herself, in her efforts to please men.
"There are many things, clever, subtle exciting things a girl may do with such a chain; some of thse were shown to me, and others I invented, sharing them with other girls at the tavern. One thing that was shown to me was the slave bridle; the male takes the light chain back between the teeth of the girl and holds it, together behind her neck, thus, too, pinning her hands there, helplessly; he then contols her by means of the bridle; my own invention was the chain kiss; one clasps the leg with the chain against the interior of the thigh, and then, from the side of the knee, one begins to kiss the leg, one's lips and teeth hot about the chain; the male feels both the chain and her mouth, biting and kissing, climbing the chain; she climbs the chain and descends it, and climbs it again, until he orders her to leave it."
Slave Girl

This slave has not received Slaver House formal training, but has learned "on the job". Her skill is much improved since the last time this man had contact with her.
"Are you as innocent and as clumsy as before?" he asked.
"No, Master," I said, putting my head down, beginning to kiss him on the side of the leg, deeply, puffing, sucking, at the hair a tiny bit.
"I see not," he said, laughing.
I looked up. "I have been taught how to please men," I said.
Slave Girl

Not a "specific kiss", these quotes simply enlightens us on an aspect of training a Man may use with his personal slave.
"You are now going to make as complete a circuit of the room as is practical," he said. "You will, where practical, kiss the walls at the corners, on each side of the corner, about five horts from the corner and about ten horts from the floor. Where you come to chests or furniture, you will treat them as extensions of the wall, kissing them at the corners, and so on. You will then return exactly to your present position."
"Yes, Master," I said.
"You may now leave," he said.
"Yes, Master," I said. "Thank you, Master." I then began my journey. The kissing of inanimate articles, such as a master's sandals, or the tiles on which he has walked, is used in teaching a girl respect and reverence. There was something of this involved in his command, the having to kiss the walls of his room, the furniture there, and such, but the form of the command was presumably motivated primarily by the consideration that compliance with it would guarantee a full and adequate negotiation of the room's interior perimeter.
I was then, after a time, again where I had been before on all fours, some ten feet from his chair, facing him. The leash, dangling from my collar, was now trailing behind me, between my legs.
Kajira

He kept me on the leash for at least twenty Ehn and, in the latter portion of this time, commanded me. It seemed as if he made me move, and posed me, in almost every way in which a strong male might desire to see a human female, and I, of course, must conform perfectly to his wishes on my leash. He even took me about the room and to his couch. He made me do such things as grind my belly against the wall of the room and throw myself, on my belly and back, over the great storage chest, wooden and iron-banded, at one side of the room. I remember the feel of the wood and iron. Too, he permitted me, even ordered me, upon his couch, there to continue my performances. I must first, of course, kneel at the lower left side of the couch and kiss the covers before being permitted to creep upon it. Then he drew me from the couch to the floor at its foot, near the slave ring. With one hand he flung covers to the floor there, on the tiles.
He then pointed to a place on the tiles, out from the covers but in front of them. "A free person has walked here," he said. "Yes, Master," I said. I then, kneeling, put down my head and kissed the indicated place three times.
Kajira