Here is a nice Soul linker quest guide for you.1
Soul linkers use their skills to allow other classes to use other skills that they normally can't or affect monsters in the same way, but negatively; this class is very party oriented because without one their skills are useless.
WARNING YOU MUST BE A TAEKOWN BOY/GIRL AT JOB LEVEL 40 TO START THIS QUEST
Another pretty hard quest just stick with me here.
Step 1: Talk to the kid who is located at the top left corner of Morroc inside a room in a pub
Basicly some bad stuff went down and he needs you to collect items; the items you need are:
|Witherless Rose x 1|
|3carat Diamond x 1|
|Immortal Heart x 1|
After you bring him the items he'll help you out.
Step 2-4 Talk to NPC at the location you're warped to
First the muscle guy, then the woman, then mister monocle. (all have "lost Soul" as their name).
Go ahead and tap enter there's nothing important.
Step 5: Go back and talk to the kid
He'll change you into a soul linker.
Step 6: Profit
You went through ANOTHER horrible ordeal, go have some tea with your new ghost friends