The fettered soul of the khan of Goshima longs for death.
Coming too close to this creature will result in your run energy, Prayer points, and finally your Life points being siphoned from you. Should you die from this, you will appear on the docks with full health and none of your items missing; it is a safe death.
The entity follows the same path repeatedly, so it is relatively easy to avoid her. Should you get caught within her area of effect, using Surge will help you leave it quickly.
If you wish to be free of this annoying entity, simply complete the Arc miniquest series.