How old is your kitten?
How old was he when he was weaned from his mother?
I believe this is a variation of a behavior problem called wool-sucking. There are a number of factors that make a kitten or cat more likely to do this. Early weaning is a likely cause and genetics also play a part. It is basically like human thumb sucking behavior. You should try some things to get the kitten to stop this behavior because it can get worse with time. It can start with sucking on you, move on to sucking on his own fur, and then soon any fuzzy item will do. Sometimes it escalates even further, and the cat starts eating non-food materials which can be a very dangerous thing to do.
Some things you can try are using bitter spray on your clothes near your neck. Grannick's bitter apple is a good one. Provide him with a wide variety of toys to provide mental stimulation. You could try getting some cat grass (the tubs of grass that grow in the house). It would give him something to chew on. Most pet stores sells these or it can be bought on-line. Anytime he starts to suck on your neck put him on the floor and ignore him.
Here is a link to a page about feline behavior problems. If you scroll down a little ways you will find wool-sucking. A little further yet, and it goes into more detail about things to try to stop the behaviors:
If you have further questions let me know. Thank you.
You're welcome- glad I could help!