I’ve been looking around but am unable to find a proper answer anywhere.
Is reputation linked to the character, or the host of the server?
For example, if I chose Kymon’s Chosen, and I joined my friend who chose Death’s Vigil, will it screw my Kymon’s good rep and reset it to zero?
It will stay individual. What will happen, is that your friend will kill kymon mobs, and you will kill deaths order mobs.