Specifically a class that prefers to NOT do mortal battle. Accomplishes his purposes by finding peaceful (or more peaceful) ways of solving situations.
The non-combatant mission type of here to do perhaps anything, but to do with without violence, without strife, without "screwing" anybody else, even the Humans. The non-combatant will have different missions, different ways of doing things, and different accomplishments.
Why he is here is a different matter, but because his intention is to accomplish it while causing no harm (of any sort) his real purpose isn't as important in determining how you will interact with him.
Warning: non-combatants are hard to manipulate, hard to trick. Even light-workers are easier to run scams on. There are theories why this is so, and probably even a True reason, but the fact is simply that it is so
Non-combatants may attempt to interact with other groups to help them accomplish their ends without undo influence or destruction upon the Humans.
They are least likely to interact well with Harvesters and Warriors, and will look askance at Imps (tricksters), though they may enjoy a good Imp's sense of humor.