Neutral

Characters that are neutral are neither friendly, as in that you cannot interact with them or use supportive spells on them, nor hostile, as in they won't attack you, unless you attack them first. If you hover an NPC that is neutral to you, their name on their name tag is displayed in yellow colour.

You cannot use supportive spells on neutral characters, but you can use offensive spells on them. Doing that will make them retaliate and go after you.