The owner of the trait can give his mark to people, with their consent. It allows for communication between everyone with the mark, provided they are in the same dimension. When communicating, the mark shows and flickers, otherwise it can be hidden or invisible.
As such, it is very useful to form clans. One other effect of the trait is the Lord's ability to instill loyalty to people with the symbol and give them orders.
The power of the trait depends on the user's affinity with it and the strength of their soul. Lords can typically have 100 followers. To give extreme orders to clansmen such as committing suicide, one must either be extremely gifted or have soul strength far surpassing the target. Otherwise, the symbol will break and the person targeted will no longer be part of the clan.